Peter Hertel
Overview Maxwell’s Dielectric permittivity equations
Definition
Kramers- Kronig Peter Hertel Relation
Onsager Relation University of Osnabr¨uck,Germany
Summary Lecture presented at Nankai University, China
http://www.home.uni-osnabrueck.de/phertel
October/November 2011 Dielectric permittivity
Peter Hertel
Overview
Maxwell’s equations
Definition
Kramers- Kronig Relation
Onsager Relation
Summary
Make it as simple as possible, but not simpler • Optics deals with the interaction of light with matter. • Light, as an electromagnetic field, obeys Maxwell’s equations. • The Lorentz force on charged particles describes the interaction of light with matter. • We recapitulate Maxwell’s equation in the presence of matter and specialize to a homogeneous non-magnetic linear medium. • We formulate the retarded response of matter to a perturbation by an electric field • It is described by the frequency-dependent susceptibility • The real part and the imaginary part of the susceptibility are intimately related. • If properly generalized to anisotropic media, the susceptibility is a symmetric tensor, provided an exteral magnetic field is reversed.
Dielectric permittivity
Peter Hertel Overview
Overview
Maxwell’s equations
Definition
Kramers- Kronig Relation
Onsager Relation
Summary • Light, as an electromagnetic field, obeys Maxwell’s equations. • The Lorentz force on charged particles describes the interaction of light with matter. • We recapitulate Maxwell’s equation in the presence of matter and specialize to a homogeneous non-magnetic linear medium. • We formulate the retarded response of matter to a perturbation by an electric field • It is described by the frequency-dependent susceptibility • The real part and the imaginary part of the susceptibility are intimately related. • If properly generalized to anisotropic media, the susceptibility is a symmetric tensor, provided an exteral magnetic field is reversed.
Dielectric permittivity
Peter Hertel Overview
Overview • Optics deals with the interaction of light with matter.
Maxwell’s equations
Definition
Kramers- Kronig Relation
Onsager Relation
Summary • The Lorentz force on charged particles describes the interaction of light with matter. • We recapitulate Maxwell’s equation in the presence of matter and specialize to a homogeneous non-magnetic linear medium. • We formulate the retarded response of matter to a perturbation by an electric field • It is described by the frequency-dependent susceptibility • The real part and the imaginary part of the susceptibility are intimately related. • If properly generalized to anisotropic media, the susceptibility is a symmetric tensor, provided an exteral magnetic field is reversed.
Dielectric permittivity
Peter Hertel Overview
Overview • Optics deals with the interaction of light with matter. Maxwell’s • Light, as an electromagnetic field, obeys Maxwell’s equations equations. Definition
Kramers- Kronig Relation
Onsager Relation
Summary • We recapitulate Maxwell’s equation in the presence of matter and specialize to a homogeneous non-magnetic linear medium. • We formulate the retarded response of matter to a perturbation by an electric field • It is described by the frequency-dependent susceptibility • The real part and the imaginary part of the susceptibility are intimately related. • If properly generalized to anisotropic media, the susceptibility is a symmetric tensor, provided an exteral magnetic field is reversed.
Dielectric permittivity
Peter Hertel Overview
Overview • Optics deals with the interaction of light with matter. Maxwell’s • Light, as an electromagnetic field, obeys Maxwell’s equations equations. Definition
Kramers- • The Lorentz force on charged particles describes the Kronig Relation interaction of light with matter.
Onsager Relation
Summary • We formulate the retarded response of matter to a perturbation by an electric field • It is described by the frequency-dependent susceptibility • The real part and the imaginary part of the susceptibility are intimately related. • If properly generalized to anisotropic media, the susceptibility is a symmetric tensor, provided an exteral magnetic field is reversed.
Dielectric permittivity
Peter Hertel Overview
Overview • Optics deals with the interaction of light with matter. Maxwell’s • Light, as an electromagnetic field, obeys Maxwell’s equations equations. Definition
Kramers- • The Lorentz force on charged particles describes the Kronig Relation interaction of light with matter.
Onsager • We recapitulate Maxwell’s equation in the presence of Relation matter and specialize to a homogeneous non-magnetic Summary linear medium. • It is described by the frequency-dependent susceptibility • The real part and the imaginary part of the susceptibility are intimately related. • If properly generalized to anisotropic media, the susceptibility is a symmetric tensor, provided an exteral magnetic field is reversed.
Dielectric permittivity
Peter Hertel Overview
Overview • Optics deals with the interaction of light with matter. Maxwell’s • Light, as an electromagnetic field, obeys Maxwell’s equations equations. Definition
Kramers- • The Lorentz force on charged particles describes the Kronig Relation interaction of light with matter.
Onsager • We recapitulate Maxwell’s equation in the presence of Relation matter and specialize to a homogeneous non-magnetic Summary linear medium. • We formulate the retarded response of matter to a perturbation by an electric field • The real part and the imaginary part of the susceptibility are intimately related. • If properly generalized to anisotropic media, the susceptibility is a symmetric tensor, provided an exteral magnetic field is reversed.
Dielectric permittivity
Peter Hertel Overview
Overview • Optics deals with the interaction of light with matter. Maxwell’s • Light, as an electromagnetic field, obeys Maxwell’s equations equations. Definition
Kramers- • The Lorentz force on charged particles describes the Kronig Relation interaction of light with matter.
Onsager • We recapitulate Maxwell’s equation in the presence of Relation matter and specialize to a homogeneous non-magnetic Summary linear medium. • We formulate the retarded response of matter to a perturbation by an electric field • It is described by the frequency-dependent susceptibility • If properly generalized to anisotropic media, the susceptibility is a symmetric tensor, provided an exteral magnetic field is reversed.
Dielectric permittivity
Peter Hertel Overview
Overview • Optics deals with the interaction of light with matter. Maxwell’s • Light, as an electromagnetic field, obeys Maxwell’s equations equations. Definition
Kramers- • The Lorentz force on charged particles describes the Kronig Relation interaction of light with matter.
Onsager • We recapitulate Maxwell’s equation in the presence of Relation matter and specialize to a homogeneous non-magnetic Summary linear medium. • We formulate the retarded response of matter to a perturbation by an electric field • It is described by the frequency-dependent susceptibility • The real part and the imaginary part of the susceptibility are intimately related. Dielectric permittivity
Peter Hertel Overview
Overview • Optics deals with the interaction of light with matter. Maxwell’s • Light, as an electromagnetic field, obeys Maxwell’s equations equations. Definition
Kramers- • The Lorentz force on charged particles describes the Kronig Relation interaction of light with matter.
Onsager • We recapitulate Maxwell’s equation in the presence of Relation matter and specialize to a homogeneous non-magnetic Summary linear medium. • We formulate the retarded response of matter to a perturbation by an electric field • It is described by the frequency-dependent susceptibility • The real part and the imaginary part of the susceptibility are intimately related. • If properly generalized to anisotropic media, the susceptibility is a symmetric tensor, provided an exteral magnetic field is reversed. 1 0∇ · E = % 2 ∇ · B = 0
3 ∇ × E = −∇t B
4 (1/µ0)∇ × B = 0 ∇t E + j
The electromagnetic field E and B accelerates charged particles
p˙ = q{E(t, x) + v × B(t, x)}
At time t, the particle is at x, has velocity v = x˙ and momentum p. Its electric charge is q.
Dielectric permittivity
Peter Hertel Maxwell’s equations
Overview
Maxwell’s equations
Definition
Kramers- Kronig Relation
Onsager Relation
Summary 1 0∇ · E = % 2 ∇ · B = 0
3 ∇ × E = −∇t B
4 (1/µ0)∇ × B = 0 ∇t E + j
p˙ = q{E(t, x) + v × B(t, x)}
At time t, the particle is at x, has velocity v = x˙ and momentum p. Its electric charge is q.
Dielectric permittivity
Peter Hertel Maxwell’s equations
Overview
Maxwell’s equations The electromagnetic field E and B accelerates charged Definition particles Kramers- Kronig Relation
Onsager Relation
Summary 1 0∇ · E = % 2 ∇ · B = 0
3 ∇ × E = −∇t B
4 (1/µ0)∇ × B = 0 ∇t E + j
At time t, the particle is at x, has velocity v = x˙ and momentum p. Its electric charge is q.
Dielectric permittivity
Peter Hertel Maxwell’s equations
Overview
Maxwell’s equations The electromagnetic field E and B accelerates charged Definition particles Kramers- Kronig Relation p˙ = q{E(t, x) + v × B(t, x)} Onsager Relation
Summary 1 0∇ · E = % 2 ∇ · B = 0
3 ∇ × E = −∇t B
4 (1/µ0)∇ × B = 0 ∇t E + j
Dielectric permittivity
Peter Hertel Maxwell’s equations
Overview
Maxwell’s equations The electromagnetic field E and B accelerates charged Definition particles Kramers- Kronig Relation p˙ = q{E(t, x) + v × B(t, x)} Onsager Relation At time t, the particle is at x, has velocity v = x˙ and Summary momentum p. Its electric charge is q. 2 ∇ · B = 0
3 ∇ × E = −∇t B
4 (1/µ0)∇ × B = 0 ∇t E + j
Dielectric permittivity
Peter Hertel Maxwell’s equations
Overview
Maxwell’s equations The electromagnetic field E and B accelerates charged Definition particles Kramers- Kronig Relation p˙ = q{E(t, x) + v × B(t, x)} Onsager Relation At time t, the particle is at x, has velocity v = x˙ and Summary momentum p. Its electric charge is q.
1 0∇ · E = % 3 ∇ × E = −∇t B
4 (1/µ0)∇ × B = 0 ∇t E + j
Dielectric permittivity
Peter Hertel Maxwell’s equations
Overview
Maxwell’s equations The electromagnetic field E and B accelerates charged Definition particles Kramers- Kronig Relation p˙ = q{E(t, x) + v × B(t, x)} Onsager Relation At time t, the particle is at x, has velocity v = x˙ and Summary momentum p. Its electric charge is q.
1 0∇ · E = % 2 ∇ · B = 0 4 (1/µ0)∇ × B = 0 ∇t E + j
Dielectric permittivity
Peter Hertel Maxwell’s equations
Overview
Maxwell’s equations The electromagnetic field E and B accelerates charged Definition particles Kramers- Kronig Relation p˙ = q{E(t, x) + v × B(t, x)} Onsager Relation At time t, the particle is at x, has velocity v = x˙ and Summary momentum p. Its electric charge is q.
1 0∇ · E = % 2 ∇ · B = 0
3 ∇ × E = −∇t B Dielectric permittivity
Peter Hertel Maxwell’s equations
Overview
Maxwell’s equations The electromagnetic field E and B accelerates charged Definition particles Kramers- Kronig Relation p˙ = q{E(t, x) + v × B(t, x)} Onsager Relation At time t, the particle is at x, has velocity v = x˙ and Summary momentum p. Its electric charge is q.
1 0∇ · E = % 2 ∇ · B = 0
3 ∇ × E = −∇t B
4 (1/µ0)∇ × B = 0 ∇t E + j • polarization P is electric dipole moment per unit volume • magnetization M is magnetic dipole moment per unit volume • electric field strength E causes polarization • magnetic induction B causes magnetization • % = −∇ · P + %f • j = P˙ + ∇ × M + jf • density %f and current density jf of free charges • a vicious circle!
Dielectric permittivity
Peter Hertel Maxwell’s equations in matter I
Overview
Maxwell’s equations
Definition
Kramers- Kronig Relation
Onsager Relation
Summary • magnetization M is magnetic dipole moment per unit volume • electric field strength E causes polarization • magnetic induction B causes magnetization • % = −∇ · P + %f • j = P˙ + ∇ × M + jf • density %f and current density jf of free charges • a vicious circle!
Dielectric permittivity
Peter Hertel Maxwell’s equations in matter I
Overview
Maxwell’s equations
Definition • polarization P is electric dipole moment per unit volume
Kramers- Kronig Relation
Onsager Relation
Summary • electric field strength E causes polarization • magnetic induction B causes magnetization • % = −∇ · P + %f • j = P˙ + ∇ × M + jf • density %f and current density jf of free charges • a vicious circle!
Dielectric permittivity
Peter Hertel Maxwell’s equations in matter I
Overview
Maxwell’s equations
Definition • polarization P is electric dipole moment per unit volume
Kramers- Kronig • magnetization M is magnetic dipole moment per unit Relation volume Onsager Relation
Summary • magnetic induction B causes magnetization • % = −∇ · P + %f • j = P˙ + ∇ × M + jf • density %f and current density jf of free charges • a vicious circle!
Dielectric permittivity
Peter Hertel Maxwell’s equations in matter I
Overview
Maxwell’s equations
Definition • polarization P is electric dipole moment per unit volume
Kramers- Kronig • magnetization M is magnetic dipole moment per unit Relation volume Onsager Relation • electric field strength E causes polarization Summary • % = −∇ · P + %f • j = P˙ + ∇ × M + jf • density %f and current density jf of free charges • a vicious circle!
Dielectric permittivity
Peter Hertel Maxwell’s equations in matter I
Overview
Maxwell’s equations
Definition • polarization P is electric dipole moment per unit volume
Kramers- Kronig • magnetization M is magnetic dipole moment per unit Relation volume Onsager Relation • electric field strength E causes polarization Summary • magnetic induction B causes magnetization • j = P˙ + ∇ × M + jf • density %f and current density jf of free charges • a vicious circle!
Dielectric permittivity
Peter Hertel Maxwell’s equations in matter I
Overview
Maxwell’s equations
Definition • polarization P is electric dipole moment per unit volume
Kramers- Kronig • magnetization M is magnetic dipole moment per unit Relation volume Onsager Relation • electric field strength E causes polarization Summary • magnetic induction B causes magnetization • % = −∇ · P + %f • density %f and current density jf of free charges • a vicious circle!
Dielectric permittivity
Peter Hertel Maxwell’s equations in matter I
Overview
Maxwell’s equations
Definition • polarization P is electric dipole moment per unit volume
Kramers- Kronig • magnetization M is magnetic dipole moment per unit Relation volume Onsager Relation • electric field strength E causes polarization Summary • magnetic induction B causes magnetization • % = −∇ · P + %f • j = P˙ + ∇ × M + jf • a vicious circle!
Dielectric permittivity
Peter Hertel Maxwell’s equations in matter I
Overview
Maxwell’s equations
Definition • polarization P is electric dipole moment per unit volume
Kramers- Kronig • magnetization M is magnetic dipole moment per unit Relation volume Onsager Relation • electric field strength E causes polarization Summary • magnetic induction B causes magnetization • % = −∇ · P + %f • j = P˙ + ∇ × M + jf • density %f and current density jf of free charges Dielectric permittivity
Peter Hertel Maxwell’s equations in matter I
Overview
Maxwell’s equations
Definition • polarization P is electric dipole moment per unit volume
Kramers- Kronig • magnetization M is magnetic dipole moment per unit Relation volume Onsager Relation • electric field strength E causes polarization Summary • magnetic induction B causes magnetization • % = −∇ · P + %f • j = P˙ + ∇ × M + jf • density %f and current density jf of free charges • a vicious circle! • introduce auxiliary field D = 0E + P • dielectric displacement
• introduce auxiliary field H = (1/µ0)B − M • magnetic field strength
1 ∇ · D = %f 2 ∇ · B = 0
3 ∇ × E = −∇t B f 4 ∇ × H = D˙ + j
Now Maxwell’s equations read
This is good – only free charges are involved and bad – there are more fields than equations
Dielectric permittivity
Peter Hertel Maxwell’s equations in matter II
Overview
Maxwell’s equations
Definition
Kramers- Kronig Relation
Onsager Relation
Summary 1 ∇ · D = %f 2 ∇ · B = 0
3 ∇ × E = −∇t B f 4 ∇ × H = D˙ + j
• dielectric displacement
• introduce auxiliary field H = (1/µ0)B − M • magnetic field strength Now Maxwell’s equations read
This is good – only free charges are involved and bad – there are more fields than equations
Dielectric permittivity
Peter Hertel Maxwell’s equations in matter II
Overview
Maxwell’s equations • introduce auxiliary field D = 0E + P Definition
Kramers- Kronig Relation
Onsager Relation
Summary 1 ∇ · D = %f 2 ∇ · B = 0
3 ∇ × E = −∇t B f 4 ∇ × H = D˙ + j
• introduce auxiliary field H = (1/µ0)B − M • magnetic field strength Now Maxwell’s equations read
This is good – only free charges are involved and bad – there are more fields than equations
Dielectric permittivity
Peter Hertel Maxwell’s equations in matter II
Overview
Maxwell’s equations • introduce auxiliary field D = 0E + P Definition • dielectric displacement Kramers- Kronig Relation
Onsager Relation
Summary 1 ∇ · D = %f 2 ∇ · B = 0
3 ∇ × E = −∇t B f 4 ∇ × H = D˙ + j
• magnetic field strength Now Maxwell’s equations read
This is good – only free charges are involved and bad – there are more fields than equations
Dielectric permittivity
Peter Hertel Maxwell’s equations in matter II
Overview
Maxwell’s equations • introduce auxiliary field D = 0E + P Definition • dielectric displacement Kramers- Kronig • introduce auxiliary field H = (1/µ0)B − M Relation
Onsager Relation
Summary 1 ∇ · D = %f 2 ∇ · B = 0
3 ∇ × E = −∇t B f 4 ∇ × H = D˙ + j
Now Maxwell’s equations read
This is good – only free charges are involved and bad – there are more fields than equations
Dielectric permittivity
Peter Hertel Maxwell’s equations in matter II
Overview
Maxwell’s equations • introduce auxiliary field D = 0E + P Definition • dielectric displacement Kramers- Kronig • introduce auxiliary field H = (1/µ0)B − M Relation
Onsager • magnetic field strength Relation
Summary 1 ∇ · D = %f 2 ∇ · B = 0
3 ∇ × E = −∇t B f 4 ∇ × H = D˙ + j
Now Maxwell’s equations read
This is good – only free charges are involved and bad – there are more fields than equations
Dielectric permittivity
Peter Hertel Maxwell’s equations in matter II
Overview
Maxwell’s equations • introduce auxiliary field D = 0E + P Definition • dielectric displacement Kramers- Kronig • introduce auxiliary field H = (1/µ0)B − M Relation
Onsager • magnetic field strength Relation
Summary 1 ∇ · D = %f 2 ∇ · B = 0
3 ∇ × E = −∇t B f 4 ∇ × H = D˙ + j
This is good – only free charges are involved and bad – there are more fields than equations
Dielectric permittivity
Peter Hertel Maxwell’s equations in matter II
Overview
Maxwell’s equations • introduce auxiliary field D = 0E + P Definition • dielectric displacement Kramers- Kronig • introduce auxiliary field H = (1/µ0)B − M Relation
Onsager • magnetic field strength Relation
Summary Now Maxwell’s equations read 2 ∇ · B = 0
3 ∇ × E = −∇t B f 4 ∇ × H = D˙ + j This is good – only free charges are involved and bad – there are more fields than equations
Dielectric permittivity
Peter Hertel Maxwell’s equations in matter II
Overview
Maxwell’s equations • introduce auxiliary field D = 0E + P Definition • dielectric displacement Kramers- Kronig • introduce auxiliary field H = (1/µ0)B − M Relation
Onsager • magnetic field strength Relation
Summary Now Maxwell’s equations read 1 ∇ · D = %f 3 ∇ × E = −∇t B f 4 ∇ × H = D˙ + j This is good – only free charges are involved and bad – there are more fields than equations
Dielectric permittivity
Peter Hertel Maxwell’s equations in matter II
Overview
Maxwell’s equations • introduce auxiliary field D = 0E + P Definition • dielectric displacement Kramers- Kronig • introduce auxiliary field H = (1/µ0)B − M Relation
Onsager • magnetic field strength Relation
Summary Now Maxwell’s equations read 1 ∇ · D = %f 2 ∇ · B = 0 f 4 ∇ × H = D˙ + j This is good – only free charges are involved and bad – there are more fields than equations
Dielectric permittivity
Peter Hertel Maxwell’s equations in matter II
Overview
Maxwell’s equations • introduce auxiliary field D = 0E + P Definition • dielectric displacement Kramers- Kronig • introduce auxiliary field H = (1/µ0)B − M Relation
Onsager • magnetic field strength Relation
Summary Now Maxwell’s equations read 1 ∇ · D = %f 2 ∇ · B = 0
3 ∇ × E = −∇t B This is good – only free charges are involved and bad – there are more fields than equations
Dielectric permittivity
Peter Hertel Maxwell’s equations in matter II
Overview
Maxwell’s equations • introduce auxiliary field D = 0E + P Definition • dielectric displacement Kramers- Kronig • introduce auxiliary field H = (1/µ0)B − M Relation
Onsager • magnetic field strength Relation
Summary Now Maxwell’s equations read 1 ∇ · D = %f 2 ∇ · B = 0
3 ∇ × E = −∇t B f 4 ∇ × H = D˙ + j This is good – only free charges are involved and bad – there are more fields than equations
Dielectric permittivity
Peter Hertel Maxwell’s equations in matter II
Overview
Maxwell’s equations • introduce auxiliary field D = 0E + P Definition • dielectric displacement Kramers- Kronig • introduce auxiliary field H = (1/µ0)B − M Relation
Onsager • magnetic field strength Relation
Summary Now Maxwell’s equations read 1 ∇ · D = %f 2 ∇ · B = 0
3 ∇ × E = −∇t B f 4 ∇ × H = D˙ + j and bad – there are more fields than equations
Dielectric permittivity
Peter Hertel Maxwell’s equations in matter II
Overview
Maxwell’s equations • introduce auxiliary field D = 0E + P Definition • dielectric displacement Kramers- Kronig • introduce auxiliary field H = (1/µ0)B − M Relation
Onsager • magnetic field strength Relation
Summary Now Maxwell’s equations read 1 ∇ · D = %f 2 ∇ · B = 0
3 ∇ × E = −∇t B f 4 ∇ × H = D˙ + j This is good – only free charges are involved Dielectric permittivity
Peter Hertel Maxwell’s equations in matter II
Overview
Maxwell’s equations • introduce auxiliary field D = 0E + P Definition • dielectric displacement Kramers- Kronig • introduce auxiliary field H = (1/µ0)B − M Relation
Onsager • magnetic field strength Relation
Summary Now Maxwell’s equations read 1 ∇ · D = %f 2 ∇ · B = 0
3 ∇ × E = −∇t B f 4 ∇ × H = D˙ + j This is good – only free charges are involved and bad – there are more fields than equations Dielectric permittivity
Peter Hertel
Overview
Maxwell’s equations
Definition
Kramers- Kronig Relation
Onsager Relation
Summary
James Clerk Maxwell, 1831-1873 • homogeneous • non-magnetic • linear
• P = 0χE • M = 0 • dielectric susceptibility χ is dimension-less number
• equivalent D = 0E • relative dielectric permittivity = 1 + χ • more precisely . . .
Assume a medium which is
Dielectric permittivity
Peter Hertel Dielectric susceptibility I
Overview
Maxwell’s equations
Definition
Kramers- Kronig Relation
Onsager Relation
Summary • homogeneous • non-magnetic • linear
• P = 0χE • M = 0 • dielectric susceptibility χ is dimension-less number
• equivalent D = 0E • relative dielectric permittivity = 1 + χ • more precisely . . .
Dielectric permittivity
Peter Hertel Dielectric susceptibility I
Overview
Maxwell’s equations Assume a medium which is Definition
Kramers- Kronig Relation
Onsager Relation
Summary • non-magnetic • linear
• P = 0χE • M = 0 • dielectric susceptibility χ is dimension-less number
• equivalent D = 0E • relative dielectric permittivity = 1 + χ • more precisely . . .
Dielectric permittivity
Peter Hertel Dielectric susceptibility I
Overview
Maxwell’s equations Assume a medium which is Definition • homogeneous Kramers- Kronig Relation
Onsager Relation
Summary • linear
• P = 0χE • M = 0 • dielectric susceptibility χ is dimension-less number
• equivalent D = 0E • relative dielectric permittivity = 1 + χ • more precisely . . .
Dielectric permittivity
Peter Hertel Dielectric susceptibility I
Overview
Maxwell’s equations Assume a medium which is Definition • homogeneous Kramers- Kronig Relation • non-magnetic
Onsager Relation
Summary • P = 0χE • M = 0 • dielectric susceptibility χ is dimension-less number
• equivalent D = 0E • relative dielectric permittivity = 1 + χ • more precisely . . .
Dielectric permittivity
Peter Hertel Dielectric susceptibility I
Overview
Maxwell’s equations Assume a medium which is Definition • homogeneous Kramers- Kronig Relation • non-magnetic
Onsager Relation • linear
Summary • M = 0 • dielectric susceptibility χ is dimension-less number
• equivalent D = 0E • relative dielectric permittivity = 1 + χ • more precisely . . .
Dielectric permittivity
Peter Hertel Dielectric susceptibility I
Overview
Maxwell’s equations Assume a medium which is Definition • homogeneous Kramers- Kronig Relation • non-magnetic
Onsager Relation • linear Summary • P = 0χE • dielectric susceptibility χ is dimension-less number
• equivalent D = 0E • relative dielectric permittivity = 1 + χ • more precisely . . .
Dielectric permittivity
Peter Hertel Dielectric susceptibility I
Overview
Maxwell’s equations Assume a medium which is Definition • homogeneous Kramers- Kronig Relation • non-magnetic
Onsager Relation • linear Summary • P = 0χE • M = 0 • equivalent D = 0E • relative dielectric permittivity = 1 + χ • more precisely . . .
Dielectric permittivity
Peter Hertel Dielectric susceptibility I
Overview
Maxwell’s equations Assume a medium which is Definition • homogeneous Kramers- Kronig Relation • non-magnetic
Onsager Relation • linear Summary • P = 0χE • M = 0 • dielectric susceptibility χ is dimension-less number • relative dielectric permittivity = 1 + χ • more precisely . . .
Dielectric permittivity
Peter Hertel Dielectric susceptibility I
Overview
Maxwell’s equations Assume a medium which is Definition • homogeneous Kramers- Kronig Relation • non-magnetic
Onsager Relation • linear Summary • P = 0χE • M = 0 • dielectric susceptibility χ is dimension-less number
• equivalent D = 0E • more precisely . . .
Dielectric permittivity
Peter Hertel Dielectric susceptibility I
Overview
Maxwell’s equations Assume a medium which is Definition • homogeneous Kramers- Kronig Relation • non-magnetic
Onsager Relation • linear Summary • P = 0χE • M = 0 • dielectric susceptibility χ is dimension-less number
• equivalent D = 0E • relative dielectric permittivity = 1 + χ Dielectric permittivity
Peter Hertel Dielectric susceptibility I
Overview
Maxwell’s equations Assume a medium which is Definition • homogeneous Kramers- Kronig Relation • non-magnetic
Onsager Relation • linear Summary • P = 0χE • M = 0 • dielectric susceptibility χ is dimension-less number
• equivalent D = 0E • relative dielectric permittivity = 1 + χ • more precisely . . . Assume linear local relation
Z P (t, x) = dτ G(τ)E(t − τ, x)
G(τ) = 0 for τ < 0
drop x Z P (t) = dτ G(τ)E(t − τ)
G is causal influence, or Green’s functions
Dielectric permittivity
Peter Hertel More precisely
Overview
Maxwell’s equations
Definition
Kramers- Kronig Relation
Onsager Relation
Summary Z P (t, x) = dτ G(τ)E(t − τ, x)
causality
G(τ) = 0 for τ < 0
drop x Z P (t) = dτ G(τ)E(t − τ)
G is causal influence, or Green’s functions
Dielectric permittivity
Peter Hertel More precisely
Overview
Maxwell’s Assume linear local relation equations
Definition
Kramers- Kronig Relation
Onsager Relation
Summary causality
G(τ) = 0 for τ < 0
drop x Z P (t) = dτ G(τ)E(t − τ)
G is causal influence, or Green’s functions
Dielectric permittivity
Peter Hertel More precisely
Overview
Maxwell’s Assume linear local relation equations
Definition
Kramers- Z Kronig P (t, x) = dτ G(τ)E(t − τ, x) Relation
Onsager Relation
Summary G(τ) = 0 for τ < 0
drop x Z P (t) = dτ G(τ)E(t − τ)
G is causal influence, or Green’s functions
Dielectric permittivity
Peter Hertel More precisely
Overview
Maxwell’s Assume linear local relation equations
Definition
Kramers- Z Kronig P (t, x) = dτ G(τ)E(t − τ, x) Relation
Onsager Relation causality Summary drop x Z P (t) = dτ G(τ)E(t − τ)
G is causal influence, or Green’s functions
Dielectric permittivity
Peter Hertel More precisely
Overview
Maxwell’s Assume linear local relation equations
Definition
Kramers- Z Kronig P (t, x) = dτ G(τ)E(t − τ, x) Relation
Onsager Relation causality Summary G(τ) = 0 for τ < 0 Z P (t) = dτ G(τ)E(t − τ)
G is causal influence, or Green’s functions
Dielectric permittivity
Peter Hertel More precisely
Overview
Maxwell’s Assume linear local relation equations
Definition
Kramers- Z Kronig P (t, x) = dτ G(τ)E(t − τ, x) Relation
Onsager Relation causality Summary G(τ) = 0 for τ < 0
drop x G is causal influence, or Green’s functions
Dielectric permittivity
Peter Hertel More precisely
Overview
Maxwell’s Assume linear local relation equations
Definition
Kramers- Z Kronig P (t, x) = dτ G(τ)E(t − τ, x) Relation
Onsager Relation causality Summary G(τ) = 0 for τ < 0
drop x Z P (t) = dτ G(τ)E(t − τ) Dielectric permittivity
Peter Hertel More precisely
Overview
Maxwell’s Assume linear local relation equations
Definition
Kramers- Z Kronig P (t, x) = dτ G(τ)E(t − τ, x) Relation
Onsager Relation causality Summary G(τ) = 0 for τ < 0
drop x Z P (t) = dτ G(τ)E(t − τ)
G is causal influence, or Green’s functions Dielectric permittivity
Peter Hertel
Overview
Maxwell’s equations
Definition
Kramers- Kronig Relation
Onsager Relation
Summary
George Green, 1793-1841 Z dω −iωt f(t) = e f˜(ω) 2π
Z +iωt f˜(ω) = dt e f(t)
convolution h = g ∗ f, i. e. Z h(t) = dτ g(τ)f(t − τ)
then
h˜(ω) =g ˜(ω)f˜(ω)
Dielectric permittivity
Peter Hertel Fourier transforms
Overview
Maxwell’s equations
Definition
Kramers- Kronig Relation
Onsager Relation
Summary Z +iωt f˜(ω) = dt e f(t)
convolution h = g ∗ f, i. e. Z h(t) = dτ g(τ)f(t − τ)
then
h˜(ω) =g ˜(ω)f˜(ω)
Dielectric permittivity
Peter Hertel Fourier transforms
Overview
Maxwell’s equations Z dω −iωt f(t) = e f˜(ω) Definition 2π Kramers- Kronig Relation
Onsager Relation
Summary convolution h = g ∗ f, i. e. Z h(t) = dτ g(τ)f(t − τ)
then
h˜(ω) =g ˜(ω)f˜(ω)
Dielectric permittivity
Peter Hertel Fourier transforms
Overview
Maxwell’s equations Z dω −iωt f(t) = e f˜(ω) Definition 2π Kramers- Kronig Relation Z Onsager +iωt Relation f˜(ω) = dt e f(t) Summary then
h˜(ω) =g ˜(ω)f˜(ω)
Dielectric permittivity
Peter Hertel Fourier transforms
Overview
Maxwell’s equations Z dω −iωt f(t) = e f˜(ω) Definition 2π Kramers- Kronig Relation Z Onsager +iωt Relation f˜(ω) = dt e f(t) Summary convolution h = g ∗ f, i. e. Z h(t) = dτ g(τ)f(t − τ) Dielectric permittivity
Peter Hertel Fourier transforms
Overview
Maxwell’s equations Z dω −iωt f(t) = e f˜(ω) Definition 2π Kramers- Kronig Relation Z Onsager +iωt Relation f˜(ω) = dt e f(t) Summary convolution h = g ∗ f, i. e. Z h(t) = dτ g(τ)f(t − τ)
then
h˜(ω) =g ˜(ω)f˜(ω) Recall Z P (t) = dτ G(τ)E(t − τ)
Therefore
P˜ (ω) = 0χ(ω)E˜ (ω) with 1 χ(ω) = G˜(ω) 0 susceptibility χ must depend on frequency ω
Dielectric permittivity
Peter Hertel Susceptibility II
Overview
Maxwell’s equations
Definition
Kramers- Kronig Relation
Onsager Relation
Summary Therefore
P˜ (ω) = 0χ(ω)E˜ (ω) with 1 χ(ω) = G˜(ω) 0 susceptibility χ must depend on frequency ω
Dielectric permittivity
Peter Hertel Susceptibility II
Overview
Maxwell’s equations Recall Definition Z Kramers- P (t) = dτ G(τ)E(t − τ) Kronig Relation
Onsager Relation
Summary susceptibility χ must depend on frequency ω
Dielectric permittivity
Peter Hertel Susceptibility II
Overview
Maxwell’s equations Recall Definition Z Kramers- P (t) = dτ G(τ)E(t − τ) Kronig Relation Onsager Therefore Relation
Summary P˜ (ω) = 0χ(ω)E˜ (ω) with 1 χ(ω) = G˜(ω) 0 Dielectric permittivity
Peter Hertel Susceptibility II
Overview
Maxwell’s equations Recall Definition Z Kramers- P (t) = dτ G(τ)E(t − τ) Kronig Relation Onsager Therefore Relation
Summary P˜ (ω) = 0χ(ω)E˜ (ω) with 1 χ(ω) = G˜(ω) 0 susceptibility χ must depend on frequency ω Recall Z P (t, x) = dτ G(τ)E(t − τ, x)
G(τ) = θ(τ)G(τ) with Heaviside function θ
Z du χ(ω) = χ(u)θ˜(ω − u) by convolution theorem 2π
1 θ˜(ω) = lim 0<η→0 η − iω
Z du χ(u) χ(ω) = lim dispersion relation 0<η→0 2π η − i(ω − u)
Dielectric permittivity
Peter Hertel Kramers-Kronig relation I
Overview
Maxwell’s equations
Definition
Kramers- Kronig Relation
Onsager Relation
Summary G(τ) = θ(τ)G(τ) with Heaviside function θ
Z du χ(ω) = χ(u)θ˜(ω − u) by convolution theorem 2π
1 θ˜(ω) = lim 0<η→0 η − iω
Z du χ(u) χ(ω) = lim dispersion relation 0<η→0 2π η − i(ω − u)
Dielectric permittivity
Peter Hertel Kramers-Kronig relation I Recall Overview Z Maxwell’s equations P (t, x) = dτ G(τ)E(t − τ, x)
Definition
Kramers- Kronig Relation
Onsager Relation
Summary Z du χ(ω) = χ(u)θ˜(ω − u) by convolution theorem 2π
1 θ˜(ω) = lim 0<η→0 η − iω
Z du χ(u) χ(ω) = lim dispersion relation 0<η→0 2π η − i(ω − u)
Dielectric permittivity
Peter Hertel Kramers-Kronig relation I Recall Overview Z Maxwell’s equations P (t, x) = dτ G(τ)E(t − τ, x)
Definition
Kramers- Kronig Relation G(τ) = θ(τ)G(τ) with Heaviside function θ Onsager Relation
Summary 1 θ˜(ω) = lim 0<η→0 η − iω
Z du χ(u) χ(ω) = lim dispersion relation 0<η→0 2π η − i(ω − u)
Dielectric permittivity
Peter Hertel Kramers-Kronig relation I Recall Overview Z Maxwell’s equations P (t, x) = dτ G(τ)E(t − τ, x)
Definition
Kramers- Kronig Relation G(τ) = θ(τ)G(τ) with Heaviside function θ Onsager Relation
Summary Z du χ(ω) = χ(u)θ˜(ω − u) by convolution theorem 2π Z du χ(u) χ(ω) = lim dispersion relation 0<η→0 2π η − i(ω − u)
Dielectric permittivity
Peter Hertel Kramers-Kronig relation I Recall Overview Z Maxwell’s equations P (t, x) = dτ G(τ)E(t − τ, x)
Definition
Kramers- Kronig Relation G(τ) = θ(τ)G(τ) with Heaviside function θ Onsager Relation
Summary Z du χ(ω) = χ(u)θ˜(ω − u) by convolution theorem 2π
1 θ˜(ω) = lim 0<η→0 η − iω Dielectric permittivity
Peter Hertel Kramers-Kronig relation I Recall Overview Z Maxwell’s equations P (t, x) = dτ G(τ)E(t − τ, x)
Definition
Kramers- Kronig Relation G(τ) = θ(τ)G(τ) with Heaviside function θ Onsager Relation
Summary Z du χ(ω) = χ(u)θ˜(ω − u) by convolution theorem 2π
1 θ˜(ω) = lim 0<η→0 η − iω
Z du χ(u) χ(ω) = lim dispersion relation 0<η→0 2π η − i(ω − u) Dielectric permittivity
Peter Hertel
Overview
Maxwell’s equations
Definition
Kramers- Kronig Relation
Onsager Relation
Summary
Dispersion of white light Decompose susceptibility in real and imaginary part χ(ω) = χ 0(ω) + iχ 00(ω) Introduce principle value integral Z du Z ω−η Z ∞ du Pr ··· = + ... 2π −∞ ω+η 2π Employ χ(−ω) = χ(ω)∗
Z du uχ 00(u) χ 0(ω) = 2Pr KKR π u2 − ω2
Z du ωχ 0(u) χ 00(ω) = 2Pr inverse KKR π ω2 − u2
Dielectric permittivity
Peter Hertel Kramers-Kronig relation II
Overview
Maxwell’s equations
Definition
Kramers- Kronig Relation
Onsager Relation
Summary Introduce principle value integral Z du Z ω−η Z ∞ du Pr ··· = + ... 2π −∞ ω+η 2π Employ χ(−ω) = χ(ω)∗
Z du uχ 00(u) χ 0(ω) = 2Pr KKR π u2 − ω2
Z du ωχ 0(u) χ 00(ω) = 2Pr inverse KKR π ω2 − u2
Dielectric permittivity
Peter Hertel Kramers-Kronig relation II Decompose susceptibility in real and imaginary part Overview Maxwell’s χ(ω) = χ 0(ω) + iχ 00(ω) equations
Definition
Kramers- Kronig Relation
Onsager Relation
Summary Employ χ(−ω) = χ(ω)∗
Z du uχ 00(u) χ 0(ω) = 2Pr KKR π u2 − ω2
Z du ωχ 0(u) χ 00(ω) = 2Pr inverse KKR π ω2 − u2
Dielectric permittivity
Peter Hertel Kramers-Kronig relation II Decompose susceptibility in real and imaginary part Overview Maxwell’s χ(ω) = χ 0(ω) + iχ 00(ω) equations Definition Introduce principle value integral Kramers- Kronig Z du Z ω−η Z ∞ du Relation Pr ··· = + ... Onsager 2π −∞ ω+η 2π Relation
Summary Z du uχ 00(u) χ 0(ω) = 2Pr KKR π u2 − ω2
Z du ωχ 0(u) χ 00(ω) = 2Pr inverse KKR π ω2 − u2
Dielectric permittivity
Peter Hertel Kramers-Kronig relation II Decompose susceptibility in real and imaginary part Overview Maxwell’s χ(ω) = χ 0(ω) + iχ 00(ω) equations Definition Introduce principle value integral Kramers- Kronig Z du Z ω−η Z ∞ du Relation Pr ··· = + ... Onsager 2π −∞ ω+η 2π Relation
Summary Employ χ(−ω) = χ(ω)∗ Z du ωχ 0(u) χ 00(ω) = 2Pr inverse KKR π ω2 − u2
Dielectric permittivity
Peter Hertel Kramers-Kronig relation II Decompose susceptibility in real and imaginary part Overview Maxwell’s χ(ω) = χ 0(ω) + iχ 00(ω) equations Definition Introduce principle value integral Kramers- Kronig Z du Z ω−η Z ∞ du Relation Pr ··· = + ... Onsager 2π −∞ ω+η 2π Relation
Summary Employ χ(−ω) = χ(ω)∗
Z du uχ 00(u) χ 0(ω) = 2Pr KKR π u2 − ω2 Dielectric permittivity
Peter Hertel Kramers-Kronig relation II Decompose susceptibility in real and imaginary part Overview Maxwell’s χ(ω) = χ 0(ω) + iχ 00(ω) equations Definition Introduce principle value integral Kramers- Kronig Z du Z ω−η Z ∞ du Relation Pr ··· = + ... Onsager 2π −∞ ω+η 2π Relation
Summary Employ χ(−ω) = χ(ω)∗
Z du uχ 00(u) χ 0(ω) = 2Pr KKR π u2 − ω2
Z du ωχ 0(u) χ 00(ω) = 2Pr inverse KKR π ω2 − u2 Dielectric permittivity
Peter Hertel
Overview
Maxwell’s equations
Definition
Kramers- Kronig Relation
Onsager Relation
Summary
Hendrik Anthony Kramers (center), Dutch physicist, 1894-1952 Dielectric permittivity
Peter Hertel
Overview
Maxwell’s equations
Definition
Kramers- Kronig Relation
Onsager Relation
Summary
Ralph Kronig, US American physicist, 1904-1995 • time reversal (t, x) → (−t, x) • consequently (v, p) → (−v, −p) • recall p˙ = q{E + v × B} • time reversal invariance requires (E, B) → (E, −B) • moreover, (%, j) → (%, −j)
1 0∇ · E = % X 2 ∇ · B = 0 X 3 ∇ × E = −∇t B X 4 (1/µ0)∇ × B = 0 ∇t E + j X
Maxwell’s equations are time reversal invariant
Dielectric permittivity
Peter Hertel Time reversal invariance
Overview
Maxwell’s equations
Definition
Kramers- Kronig Relation
Onsager Relation
Summary • consequently (v, p) → (−v, −p) • recall p˙ = q{E + v × B} • time reversal invariance requires (E, B) → (E, −B) • moreover, (%, j) → (%, −j)
1 0∇ · E = % X 2 ∇ · B = 0 X 3 ∇ × E = −∇t B X 4 (1/µ0)∇ × B = 0 ∇t E + j X Maxwell’s equations are time reversal invariant
Dielectric permittivity
Peter Hertel Time reversal invariance
Overview
Maxwell’s equations • time reversal (t, x) → (−t, x) Definition
Kramers- Kronig Relation
Onsager Relation
Summary • recall p˙ = q{E + v × B} • time reversal invariance requires (E, B) → (E, −B) • moreover, (%, j) → (%, −j)
1 0∇ · E = % X 2 ∇ · B = 0 X 3 ∇ × E = −∇t B X 4 (1/µ0)∇ × B = 0 ∇t E + j X Maxwell’s equations are time reversal invariant
Dielectric permittivity
Peter Hertel Time reversal invariance
Overview
Maxwell’s equations • time reversal (t, x) → (−t, x) Definition • consequently (v, p) → (−v, −p) Kramers- Kronig Relation
Onsager Relation
Summary • time reversal invariance requires (E, B) → (E, −B) • moreover, (%, j) → (%, −j)
1 0∇ · E = % X 2 ∇ · B = 0 X 3 ∇ × E = −∇t B X 4 (1/µ0)∇ × B = 0 ∇t E + j X Maxwell’s equations are time reversal invariant
Dielectric permittivity
Peter Hertel Time reversal invariance
Overview
Maxwell’s equations • time reversal (t, x) → (−t, x) Definition • consequently (v, p) → (−v, −p) Kramers- Kronig • recall p˙ = q{E + v × B} Relation
Onsager Relation
Summary • moreover, (%, j) → (%, −j)
1 0∇ · E = % X 2 ∇ · B = 0 X 3 ∇ × E = −∇t B X 4 (1/µ0)∇ × B = 0 ∇t E + j X Maxwell’s equations are time reversal invariant
Dielectric permittivity
Peter Hertel Time reversal invariance
Overview
Maxwell’s equations • time reversal (t, x) → (−t, x) Definition • consequently (v, p) → (−v, −p) Kramers- Kronig • recall p˙ = q{E + v × B} Relation
Onsager • time reversal invariance requires (E, B) → (E, −B) Relation
Summary 1 0∇ · E = % X 2 ∇ · B = 0 X 3 ∇ × E = −∇t B X 4 (1/µ0)∇ × B = 0 ∇t E + j X Maxwell’s equations are time reversal invariant
Dielectric permittivity
Peter Hertel Time reversal invariance
Overview
Maxwell’s equations • time reversal (t, x) → (−t, x) Definition • consequently (v, p) → (−v, −p) Kramers- Kronig • recall p˙ = q{E + v × B} Relation
Onsager • time reversal invariance requires (E, B) → (E, −B) Relation • moreover, (%, j) → (%, −j) Summary 2 ∇ · B = 0 X 3 ∇ × E = −∇t B X 4 (1/µ0)∇ × B = 0 ∇t E + j X Maxwell’s equations are time reversal invariant
Dielectric permittivity
Peter Hertel Time reversal invariance
Overview
Maxwell’s equations • time reversal (t, x) → (−t, x) Definition • consequently (v, p) → (−v, −p) Kramers- Kronig • recall p˙ = q{E + v × B} Relation
Onsager • time reversal invariance requires (E, B) → (E, −B) Relation • moreover, (%, j) → (%, −j) Summary
1 0∇ · E = % X 3 ∇ × E = −∇t B X 4 (1/µ0)∇ × B = 0 ∇t E + j X Maxwell’s equations are time reversal invariant
Dielectric permittivity
Peter Hertel Time reversal invariance
Overview
Maxwell’s equations • time reversal (t, x) → (−t, x) Definition • consequently (v, p) → (−v, −p) Kramers- Kronig • recall p˙ = q{E + v × B} Relation
Onsager • time reversal invariance requires (E, B) → (E, −B) Relation • moreover, (%, j) → (%, −j) Summary
1 0∇ · E = % X 2 ∇ · B = 0 X 4 (1/µ0)∇ × B = 0 ∇t E + j X Maxwell’s equations are time reversal invariant
Dielectric permittivity
Peter Hertel Time reversal invariance
Overview
Maxwell’s equations • time reversal (t, x) → (−t, x) Definition • consequently (v, p) → (−v, −p) Kramers- Kronig • recall p˙ = q{E + v × B} Relation
Onsager • time reversal invariance requires (E, B) → (E, −B) Relation • moreover, (%, j) → (%, −j) Summary
1 0∇ · E = % X 2 ∇ · B = 0 X 3 ∇ × E = −∇t B X Maxwell’s equations are time reversal invariant
Dielectric permittivity
Peter Hertel Time reversal invariance
Overview
Maxwell’s equations • time reversal (t, x) → (−t, x) Definition • consequently (v, p) → (−v, −p) Kramers- Kronig • recall p˙ = q{E + v × B} Relation
Onsager • time reversal invariance requires (E, B) → (E, −B) Relation • moreover, (%, j) → (%, −j) Summary
1 0∇ · E = % X 2 ∇ · B = 0 X 3 ∇ × E = −∇t B X 4 (1/µ0)∇ × B = 0 ∇t E + j X Maxwell’s equations are time reversal invariant
Dielectric permittivity
Peter Hertel Time reversal invariance
Overview
Maxwell’s equations • time reversal (t, x) → (−t, x) Definition • consequently (v, p) → (−v, −p) Kramers- Kronig • recall p˙ = q{E + v × B} Relation
Onsager • time reversal invariance requires (E, B) → (E, −B) Relation • moreover, (%, j) → (%, −j) Summary
1 0∇ · E = % X 2 ∇ · B = 0 X 3 ∇ × E = −∇t B X 4 (1/µ0)∇ × B = 0 ∇t E + j X Dielectric permittivity
Peter Hertel Time reversal invariance
Overview
Maxwell’s equations • time reversal (t, x) → (−t, x) Definition • consequently (v, p) → (−v, −p) Kramers- Kronig • recall p˙ = q{E + v × B} Relation
Onsager • time reversal invariance requires (E, B) → (E, −B) Relation • moreover, (%, j) → (%, −j) Summary
1 0∇ · E = % X 2 ∇ · B = 0 X 3 ∇ × E = −∇t B X 4 (1/µ0)∇ × B = 0 ∇t E + j X Maxwell’s equations are time reversal invariant • generalize to a possible anisotropic medium
• P˜i(ω) = χij(ω)E˜j(ω) (sum over j = 1, 2, 3) • susceptibility is a property of matter in thermal equilibrium • its value depends on all parameters which affect the equilibrium • such as temperature, mechanical strain, external static electric or magnetic fields, . . .
• χij = χij(ω; T, S, E, B,... ) • Interchanging indexes and reverting B is a symmetry
• χij(ω; T, S, E, B,... ) = χji(ω; T, S, E, −B,... )
Dielectric permittivity
Peter Hertel Onsager symmetry relation
Overview
Maxwell’s equations
Definition
Kramers- Kronig Relation
Onsager Relation
Summary • P˜i(ω) = χij(ω)E˜j(ω) (sum over j = 1, 2, 3) • susceptibility is a property of matter in thermal equilibrium • its value depends on all parameters which affect the equilibrium • such as temperature, mechanical strain, external static electric or magnetic fields, . . .
• χij = χij(ω; T, S, E, B,... ) • Interchanging indexes and reverting B is a symmetry
• χij(ω; T, S, E, B,... ) = χji(ω; T, S, E, −B,... )
Dielectric permittivity
Peter Hertel Onsager symmetry relation
Overview
Maxwell’s equations • generalize to a possible anisotropic medium Definition
Kramers- Kronig Relation
Onsager Relation
Summary • susceptibility is a property of matter in thermal equilibrium • its value depends on all parameters which affect the equilibrium • such as temperature, mechanical strain, external static electric or magnetic fields, . . .
• χij = χij(ω; T, S, E, B,... ) • Interchanging indexes and reverting B is a symmetry
• χij(ω; T, S, E, B,... ) = χji(ω; T, S, E, −B,... )
Dielectric permittivity
Peter Hertel Onsager symmetry relation
Overview
Maxwell’s equations • generalize to a possible anisotropic medium Definition ˜ ˜ Kramers- • Pi(ω) = χij(ω)Ej(ω) (sum over j = 1, 2, 3) Kronig Relation
Onsager Relation
Summary • its value depends on all parameters which affect the equilibrium • such as temperature, mechanical strain, external static electric or magnetic fields, . . .
• χij = χij(ω; T, S, E, B,... ) • Interchanging indexes and reverting B is a symmetry
• χij(ω; T, S, E, B,... ) = χji(ω; T, S, E, −B,... )
Dielectric permittivity
Peter Hertel Onsager symmetry relation
Overview
Maxwell’s equations • generalize to a possible anisotropic medium Definition ˜ ˜ Kramers- • Pi(ω) = χij(ω)Ej(ω) (sum over j = 1, 2, 3) Kronig Relation • susceptibility is a property of matter in thermal equilibrium
Onsager Relation
Summary • such as temperature, mechanical strain, external static electric or magnetic fields, . . .
• χij = χij(ω; T, S, E, B,... ) • Interchanging indexes and reverting B is a symmetry
• χij(ω; T, S, E, B,... ) = χji(ω; T, S, E, −B,... )
Dielectric permittivity
Peter Hertel Onsager symmetry relation
Overview
Maxwell’s equations • generalize to a possible anisotropic medium Definition ˜ ˜ Kramers- • Pi(ω) = χij(ω)Ej(ω) (sum over j = 1, 2, 3) Kronig Relation • susceptibility is a property of matter in thermal equilibrium Onsager • Relation its value depends on all parameters which affect the
Summary equilibrium • χij = χij(ω; T, S, E, B,... ) • Interchanging indexes and reverting B is a symmetry
• χij(ω; T, S, E, B,... ) = χji(ω; T, S, E, −B,... )
Dielectric permittivity
Peter Hertel Onsager symmetry relation
Overview
Maxwell’s equations • generalize to a possible anisotropic medium Definition ˜ ˜ Kramers- • Pi(ω) = χij(ω)Ej(ω) (sum over j = 1, 2, 3) Kronig Relation • susceptibility is a property of matter in thermal equilibrium Onsager • Relation its value depends on all parameters which affect the
Summary equilibrium • such as temperature, mechanical strain, external static electric or magnetic fields, . . . • Interchanging indexes and reverting B is a symmetry
• χij(ω; T, S, E, B,... ) = χji(ω; T, S, E, −B,... )
Dielectric permittivity
Peter Hertel Onsager symmetry relation
Overview
Maxwell’s equations • generalize to a possible anisotropic medium Definition ˜ ˜ Kramers- • Pi(ω) = χij(ω)Ej(ω) (sum over j = 1, 2, 3) Kronig Relation • susceptibility is a property of matter in thermal equilibrium Onsager • Relation its value depends on all parameters which affect the
Summary equilibrium • such as temperature, mechanical strain, external static electric or magnetic fields, . . .
• χij = χij(ω; T, S, E, B,... ) • χij(ω; T, S, E, B,... ) = χji(ω; T, S, E, −B,... )
Dielectric permittivity
Peter Hertel Onsager symmetry relation
Overview
Maxwell’s equations • generalize to a possible anisotropic medium Definition ˜ ˜ Kramers- • Pi(ω) = χij(ω)Ej(ω) (sum over j = 1, 2, 3) Kronig Relation • susceptibility is a property of matter in thermal equilibrium Onsager • Relation its value depends on all parameters which affect the
Summary equilibrium • such as temperature, mechanical strain, external static electric or magnetic fields, . . .
• χij = χij(ω; T, S, E, B,... ) • Interchanging indexes and reverting B is a symmetry Dielectric permittivity
Peter Hertel Onsager symmetry relation
Overview
Maxwell’s equations • generalize to a possible anisotropic medium Definition ˜ ˜ Kramers- • Pi(ω) = χij(ω)Ej(ω) (sum over j = 1, 2, 3) Kronig Relation • susceptibility is a property of matter in thermal equilibrium Onsager • Relation its value depends on all parameters which affect the
Summary equilibrium • such as temperature, mechanical strain, external static electric or magnetic fields, . . .
• χij = χij(ω; T, S, E, B,... ) • Interchanging indexes and reverting B is a symmetry
• χij(ω; T, S, E, B,... ) = χji(ω; T, S, E, −B,... ) Dielectric permittivity
Peter Hertel
Overview
Maxwell’s equations
Definition
Kramers- Kronig Relation
Onsager Relation
Summary
Lars Onsager, Norwegian/US American physical chemist, 1903-1976 • Optics deals with the interaction of light with matter. • Light, as an electromagnetic field, obeys Maxwell’s equations. • The Lorentz force on charged particles describes the interaction of light with matter. • We recapitulated Maxwell’s equation in the presence of matter and specialized to a homogeneous non-magnetic linear medium. • We described the retarded response of matter to a perturbation by an electric field • It is described by the frequency-dependent susceptibility • The real part and the imaginary part of the susceptibility are intimately related (Kramers-Kronig). • If properly generalized to anisotropic media, the susceptibility is a symmetric tensor, provided an exteral magnetic field is reversed (Onsager).
Dielectric permittivity
Peter Hertel Summary
Overview
Maxwell’s equations
Definition
Kramers- Kronig Relation
Onsager Relation
Summary • Light, as an electromagnetic field, obeys Maxwell’s equations. • The Lorentz force on charged particles describes the interaction of light with matter. • We recapitulated Maxwell’s equation in the presence of matter and specialized to a homogeneous non-magnetic linear medium. • We described the retarded response of matter to a perturbation by an electric field • It is described by the frequency-dependent susceptibility • The real part and the imaginary part of the susceptibility are intimately related (Kramers-Kronig). • If properly generalized to anisotropic media, the susceptibility is a symmetric tensor, provided an exteral magnetic field is reversed (Onsager).
Dielectric permittivity
Peter Hertel Summary
Overview • Optics deals with the interaction of light with matter.
Maxwell’s equations
Definition
Kramers- Kronig Relation
Onsager Relation
Summary • The Lorentz force on charged particles describes the interaction of light with matter. • We recapitulated Maxwell’s equation in the presence of matter and specialized to a homogeneous non-magnetic linear medium. • We described the retarded response of matter to a perturbation by an electric field • It is described by the frequency-dependent susceptibility • The real part and the imaginary part of the susceptibility are intimately related (Kramers-Kronig). • If properly generalized to anisotropic media, the susceptibility is a symmetric tensor, provided an exteral magnetic field is reversed (Onsager).
Dielectric permittivity
Peter Hertel Summary
Overview • Optics deals with the interaction of light with matter. Maxwell’s • Light, as an electromagnetic field, obeys Maxwell’s equations equations. Definition
Kramers- Kronig Relation
Onsager Relation
Summary • We recapitulated Maxwell’s equation in the presence of matter and specialized to a homogeneous non-magnetic linear medium. • We described the retarded response of matter to a perturbation by an electric field • It is described by the frequency-dependent susceptibility • The real part and the imaginary part of the susceptibility are intimately related (Kramers-Kronig). • If properly generalized to anisotropic media, the susceptibility is a symmetric tensor, provided an exteral magnetic field is reversed (Onsager).
Dielectric permittivity
Peter Hertel Summary
Overview • Optics deals with the interaction of light with matter. Maxwell’s • Light, as an electromagnetic field, obeys Maxwell’s equations equations. Definition
Kramers- • The Lorentz force on charged particles describes the Kronig Relation interaction of light with matter.
Onsager Relation
Summary • We described the retarded response of matter to a perturbation by an electric field • It is described by the frequency-dependent susceptibility • The real part and the imaginary part of the susceptibility are intimately related (Kramers-Kronig). • If properly generalized to anisotropic media, the susceptibility is a symmetric tensor, provided an exteral magnetic field is reversed (Onsager).
Dielectric permittivity
Peter Hertel Summary
Overview • Optics deals with the interaction of light with matter. Maxwell’s • Light, as an electromagnetic field, obeys Maxwell’s equations equations. Definition
Kramers- • The Lorentz force on charged particles describes the Kronig Relation interaction of light with matter.
Onsager • We recapitulated Maxwell’s equation in the presence of Relation matter and specialized to a homogeneous non-magnetic Summary linear medium. • It is described by the frequency-dependent susceptibility • The real part and the imaginary part of the susceptibility are intimately related (Kramers-Kronig). • If properly generalized to anisotropic media, the susceptibility is a symmetric tensor, provided an exteral magnetic field is reversed (Onsager).
Dielectric permittivity
Peter Hertel Summary
Overview • Optics deals with the interaction of light with matter. Maxwell’s • Light, as an electromagnetic field, obeys Maxwell’s equations equations. Definition
Kramers- • The Lorentz force on charged particles describes the Kronig Relation interaction of light with matter.
Onsager • We recapitulated Maxwell’s equation in the presence of Relation matter and specialized to a homogeneous non-magnetic Summary linear medium. • We described the retarded response of matter to a perturbation by an electric field • The real part and the imaginary part of the susceptibility are intimately related (Kramers-Kronig). • If properly generalized to anisotropic media, the susceptibility is a symmetric tensor, provided an exteral magnetic field is reversed (Onsager).
Dielectric permittivity
Peter Hertel Summary
Overview • Optics deals with the interaction of light with matter. Maxwell’s • Light, as an electromagnetic field, obeys Maxwell’s equations equations. Definition
Kramers- • The Lorentz force on charged particles describes the Kronig Relation interaction of light with matter.
Onsager • We recapitulated Maxwell’s equation in the presence of Relation matter and specialized to a homogeneous non-magnetic Summary linear medium. • We described the retarded response of matter to a perturbation by an electric field • It is described by the frequency-dependent susceptibility • If properly generalized to anisotropic media, the susceptibility is a symmetric tensor, provided an exteral magnetic field is reversed (Onsager).
Dielectric permittivity
Peter Hertel Summary
Overview • Optics deals with the interaction of light with matter. Maxwell’s • Light, as an electromagnetic field, obeys Maxwell’s equations equations. Definition
Kramers- • The Lorentz force on charged particles describes the Kronig Relation interaction of light with matter.
Onsager • We recapitulated Maxwell’s equation in the presence of Relation matter and specialized to a homogeneous non-magnetic Summary linear medium. • We described the retarded response of matter to a perturbation by an electric field • It is described by the frequency-dependent susceptibility • The real part and the imaginary part of the susceptibility are intimately related (Kramers-Kronig). Dielectric permittivity
Peter Hertel Summary
Overview • Optics deals with the interaction of light with matter. Maxwell’s • Light, as an electromagnetic field, obeys Maxwell’s equations equations. Definition
Kramers- • The Lorentz force on charged particles describes the Kronig Relation interaction of light with matter.
Onsager • We recapitulated Maxwell’s equation in the presence of Relation matter and specialized to a homogeneous non-magnetic Summary linear medium. • We described the retarded response of matter to a perturbation by an electric field • It is described by the frequency-dependent susceptibility • The real part and the imaginary part of the susceptibility are intimately related (Kramers-Kronig). • If properly generalized to anisotropic media, the susceptibility is a symmetric tensor, provided an exteral magnetic field is reversed (Onsager).