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James Clerk Maxwell
James Clerk Maxwell JAMES CLERK MAXWELL Perspectives on his Life and Work Edited by raymond flood mark mccartney and andrew whitaker 3 3 Great Clarendon Street, Oxford, OX2 6DP, United Kingdom Oxford University Press is a department of the University of Oxford. It furthers the University’s objective of excellence in research, scholarship, and education by publishing worldwide. Oxford is a registered trade mark of Oxford University Press in the UK and in certain other countries c Oxford University Press 2014 The moral rights of the authors have been asserted First Edition published in 2014 Impression: 1 All rights reserved. No part of this publication may be reproduced, stored in a retrieval system, or transmitted, in any form or by any means, without the prior permission in writing of Oxford University Press, or as expressly permitted by law, by licence or under terms agreed with the appropriate reprographics rights organization. Enquiries concerning reproduction outside the scope of the above should be sent to the Rights Department, Oxford University Press, at the address above You must not circulate this work in any other form and you must impose this same condition on any acquirer Published in the United States of America by Oxford University Press 198 Madison Avenue, New York, NY 10016, United States of America British Library Cataloguing in Publication Data Data available Library of Congress Control Number: 2013942195 ISBN 978–0–19–966437–5 Printed and bound by CPI Group (UK) Ltd, Croydon, CR0 4YY Links to third party websites are provided by Oxford in good faith and for information only. -
Lab 8: Polarization of Light
Lab 8: Polarization of Light 1 Introduction Refer to Appendix D for photos of the appara- tus Polarization is a fundamental property of light and a very important concept of physical optics. Not all sources of light are polarized; for instance, light from an ordinary light bulb is not polarized. In addition to unpolarized light, there is partially polarized light and totally polarized light. Light from a rainbow, reflected sunlight, and coherent laser light are examples of po- larized light. There are three di®erent types of po- larization states: linear, circular and elliptical. Each of these commonly encountered states is characterized Figure 1: (a)Oscillation of E vector, (b)An electromagnetic by a di®ering motion of the electric ¯eld vector with ¯eld. respect to the direction of propagation of the light wave. It is useful to be able to di®erentiate between 2 Background the di®erent types of polarization. Some common de- vices for measuring polarization are linear polarizers and retarders. Polaroid sunglasses are examples of po- Light is a transverse electromagnetic wave. Its prop- larizers. They block certain radiations such as glare agation can therefore be explained by recalling the from reflected sunlight. Polarizers are useful in ob- properties of transverse waves. Picture a transverse taining and analyzing linear polarization. Retarders wave as traced by a point that oscillates sinusoidally (also called wave plates) can alter the type of polar- in a plane, such that the direction of oscillation is ization and/or rotate its direction. They are used in perpendicular to the direction of propagation of the controlling and analyzing polarization states. -
Static and Dynamic Effects of Chirality in Dielectric Media
Static and dynamic effects of chirality in dielectric media R. S. Lakes Department of Engineering Physics, Department of Materials Science, University of Wisconsin, 1500 Engineering Drive, Madison, WI 53706-1687 [email protected] January 31, 2017 adapted from R. S. Lakes, Modern Physics Letters B, 30 (24) 1650319 (9 pages) (2016). Abstract Chiral dielectrics are considered from the perspective of continuum representations of spatial heterogeneity. Static effects in isotropic chiral dielectrics are predicted, provided the electric field has nonzero third spatial derivatives. The effects are compared with static chiral phenomena in Cosserat elastic materials which obey generalized continuum constitutive equations. Dynamic monopole - like magnetic induction is predicted in chiral dielectric media. keywords: chirality, dielectric, Cosserat 1 Introduction Chirality is well known in electromagnetics 1; it gives rise to optical activity in which left or right handed cir- cularly polarized waves propagate at different velocities. Known effects are dynamic only; there is considered to be no static effect 2. The constitutive equations for a directionally isotropic chiral material are 3, 4. @H D = kE − g (1) @t @E B = µH + g (2) @t in which E is electric field, D is electric displacement, B is magnetic field, H is magnetic induction, k is the dielectric permittivity, µ is magnetic permeability and g is a measure of the chirality. Optical rotation of polarized light of wavelength λ by an angle Φ (in radians per meter) is given by Φ = (2π/λ)2cg with c as the speed of light. The quantity g embodies the length scale of the chiral structure because cg has dimensions of length. -
Principles of Retarders
Polarizers PRINCIPLES OF RETARDERS etarders are used in applications where control or Ranalysis of polarization states is required. Our retarder products include innovative polymer and liquid crystal materials. Crystalline materials such as quartz and Retarders magnesium fluoride are also available upon request. Please call for a custom quote. A retarder (or waveplate) is an optical device that resolves a light wave into two orthogonal linear polarization components and produces a phase shift between them. The resulting light wave is generally of a different polarization form. Ideally, retarders do not polarize, nor do they induce an intensity change in the Crystals Liquid light beam, they simply change its polarization form. state. The transmitted light leaves the retarder elliptically All standard catalog Meadowlark Optics’ retarders are polarized. made from birefringent, uniaxial materials having two Retardance (in waves) is given by: different refractive indices – the extraordinary index ne = tր and the ordinary index no. Light traveling through a retarder has a velocity v where: dependent upon its polarization direction given by  = birefringence (ne - no) Spatial Light Modulators v = c/n = wavelength of incident light (in nanometers) t = thickness of birefringent element where c is the speed of light in a vacuum and n is the (in nanometers) refractive index parallel to that polarization direction. Retardance can also be expressed in units of length, the By definition, ne > no for a positive uniaxial material. distance that one polarization component is delayed For a positive uniaxial material, the extraordinary axis relative to the other. Retardance is then represented by: is referred to as the slow axis, while the ordinary axis is ␦Ј ␦  referred to as the fast axis. -
Circular Polarization and Nonreciprocal Propagation in Magnetic Media Circular Polarization and Nonreciprocal Propagation in Magnetic Media Gerald F
• DIONNE, ALLEN, Haddad, ROSS, AND LaX Circular Polarization and Nonreciprocal Propagation in Magnetic Media Circular Polarization and Nonreciprocal Propagation in Magnetic Media Gerald F. Dionne, Gary A. Allen, Pamela R. Haddad, Caroline A. Ross, and Benjamin Lax n The polarization of electromagnetic signals is an important feature in the design of modern radar and telecommunications. Standard electromagnetic theory readily shows that a linearly polarized plane wave propagating in free space consists of two equal but counter-rotating components of circular polarization. In magnetized media, these circular modes can be arranged to produce the nonreciprocal propagation effects that are the basic properties of isolator and circulator devices. Independent phase control of right-hand (+) and left-hand (–) circular waves is accomplished by splitting their propagation velocities through differences in the e±m± parameter. A phenomenological analysis of the permeability m and permittivity e in dispersive media serves to introduce the corresponding magnetic- and electric-dipole mechanisms of interaction length with the propagating signal. As an example of permeability dispersion, a Lincoln Laboratory quasi-optical Faraday- rotation isolator circulator at 35 GHz (l ~ 1 cm) with a garnet-ferrite rotator element is described. At infrared wavelengths (l = 1.55 mm), where fiber-optic laser sources also require protection by passive isolation of the Faraday-rotation principle, e rather than m provides the dispersion, and the frequency is limited to the quantum energies of the electric-dipole atomic transitions peculiar to the molecular structure of the magnetic garnet. For optimum performance, bismuth additions to the garnet chemical formula are usually necessary. Spectroscopic and molecular theory models developed at Lincoln Laboratory to explain the bismuth effects are reviewed. -
Polarization Phenomena of Certain Fluorites
142 TIIE AMERICAN MINERALOGIST Pleochroic,e :colorless, ,:pale blue-green, It thus differs from the average vesuvianite only in slightly higher birefringence. The writer wishes to acknowledge his indebtedness to Col. Roebling, Mr. Gage, and Ward's Natural ScienceEstablishment for the privilege of examining specimensand to Dr. Larsen for the opticaldeterminations. POLARIZATION PHENOMENA OF CERTAIN FLUORITES A. L. PansoNs, Uniaersity oJ Toronto While determining the refractive index of fluorite by the method of minimum deviation the writer introduced a nicol prism before the telescopeof the goniometer to determine the plane of polarization of the refracted ray. On rotating the nicol no difference in the intensity of light could be observed,but on examining the reflected ray nearly complete polarization was obtained so that it was thought that the prism was not cut at the angle that should give polarization if Brewster's law applies to isometric crystals. A new prism was then cut from a crystal of fluorite from Madoc, Ontario, so that the angle between the reflected ray and the refracted ray should be ninety degrees. With this new prism the same phenomena were observed. A second nicol was now intro- duced between the collimator and the crystal so that the signal was extinguished. On rotating the two nicols simultaneously extinction was obtained throughout a complete rotation so that it would appear as though we may accept without question the state- ment that a ray of light passing through fluorite vibrates with equal facility in all directions at right angles to the direction of propagation and is not polarized. -
GEOL 221 Mineralogy and Mineral Optics Course Syllabus
SAN DIEGO STATE UNIVERSITY GEOL 221 Mineralogy and Mineral Optics Course Syllabus Instructor: Professor David L. Kimbrough Email: [email protected], Phone: 594-1385 Lecture: MW 1000-1050 CSL 422, Lab: W 1400-1640, Lab study: M 1400-1640 CSL 425 Office: GMCS-229A; Office hours: MW 1100-1200; T 1115-1215; by appointment TA: Mark Nahabidian GMCS-133 TBA Course Prerequisite: Chem 200 or concurrent registration. Credit or concurrent registration in OCEAN 100 or GEOL 100 and 101 or GEOL 104 and 101; Geol 200; Required Texts: Introduction to Mineralogy, William D. Nesse, Oxford University Press. Minerals in Thin Section, Perkins & Henke, Prentice Hall Recommended Text: Dictionary of Geological Terms, AGI Bates & Jackson eds. or similar, The Complete Guide to Rocks & Minerals by John Farndon or similar Other required materials: Hand lens; calculator Classroom management: Attendance is crucial. Please let me know if you’re going to be absent for any reason. Be on time for class, don’t participate in excessive side-chatter or cause disruptions during class. Always respond to the instructor, the Teaching Assistant, and your fellow students in a respectful and civil manner. Cheating or plagiarism is not tolerated. It’s easy to spot and constitutes serious academic misconduct. Helpful hints to make Mineralogy easier and more fun! Attend class: Studies show that the most valuable time commitment by students in a course is the time actually spent in the classroom. Class time is the most important determinant of student success and yields the greatest improvement in student learning outcomes. Information is covered in class that is not in the textbook, and parts of the book are hard to understand. -
Huygen's Explanation of Double Refraction
06/08/2018 Before this lecture there were two lectures: 1. Introduction about this course. 2. Qualitative description about the various polarizations. Retarders • In retarders, one polarization gets ‘retarded’, or delayed, with respect to the other one. There is a final phase difference between the 2 components of the polarization. Therefore, the polarization is changed. • Most retarders are based on birefringent materials (quartz, mica, polymers) that have different indices of refraction depending on the polarization of the incoming light. 3 Phase shift of half wavelength Quarter Wave plate Circular polarization (IV) 7 How to generate Polarized Light? 1.Dichroic materials 2.Polarizer 3.Birefringent materials 4.Reflection 5.Scattering Wire grid polarizer Polaroid How to generate Polarized Light? 1.Dichroic materials 2.Polarizer 3.Birefringent materials 4.Reflection 5.Scattering Birefringence How to generate Polarized Light? 1.Dichroic materials 2.Polarizer 3.Birefringent materials 4.Reflection 5.Scattering Polarized Reflecting Light • When an unpolarized light wave reflects off a non-metallic surface, it can be completely polarized, partially polarized or unpolarized depending on the angle of incidence. A completely polarized wave occurs for an angle called Brewster’s angle (named after Sir David Brewster) Snell's law Incident Reflected ray ray p n 90o 1 n2 r n1sin P = n2sin r n1sin P = n2sin r = n2sin (90-P) = n2cos P tan P = n2/n1 P = Brewster’s angel Reflection • When an unpolarized wave reflects off a nonmetallic surface, the reflected wave is partially plane polarized parallel to the surface. The amount of polarization depends upon the angle (more later). The reflected ray contains more vibrations parallel to the reflecting surface while the transmitted beam contains more vibrations at right angles to these. -
Polarized Light 1
EE485 Introduction to Photonics Polarized Light 1. Matrix treatment of polarization 2. Reflection and refraction at dielectric interfaces (Fresnel equations) 3. Polarization phenomena and devices Reading: Pedrotti3, Chapter 14, Sec. 15.1-15.2, 15.4-15.6, 17.5, 23.1-23.5 Polarization of Light Polarization: Time trajectory of the end point of the electric field direction. Assume the light ray travels in +z-direction. At a particular instance, Ex ˆˆEExy y ikz() t x EEexx 0 ikz() ty EEeyy 0 iixxikz() t Ex[]ˆˆEe00xy y Ee e ikz() t E0e Lih Y. Lin 2 One Application: Creating 3-D Images Code left- and right-eye paths with orthogonal polarizations. K. Iizuka, “Welcome to the wonderful world of 3D,” OSA Optics and Photonics News, p. 41-47, Oct. 2006. Lih Y. Lin 3 Matrix Representation ― Jones Vectors Eeix E0x 0x E0 E iy 0 y Ee0 y Linearly polarized light y y 0 1 x E0 x E0 1 0 Ẽ and Ẽ must be in phase. y 0x 0y x cos E0 sin (Note: Jones vectors are normalized.) Lih Y. Lin 4 Jones Vector ― Circular Polarization Left circular polarization y x EEe it EA cos t At z = 0, compare xx0 with x it() EAsin tA ( cos( t / 2)) EEeyy 0 y 1 1 yxxy /2, 0, E00 EA Jones vector = 2 i y Right circular polarization 1 1 x Jones vector = 2 i Lih Y. Lin 5 Jones Vector ― Elliptical Polarization Special cases: Counter-clockwise rotation 1 A Jones vector = AB22 iB Clockwise rotation 1 A Jones vector = AB22 iB General case: Eeix A 0x A B22C E0 i y bei B iC Ee0 y Jones vector = 1 A A ABC222 B iC 2cosEE00xy tan 2 22 EE00xy Lih Y. -
Wave Optics Experiment 1: Microwave Standing Waves
Wave Optics This project includes four independent experiments. The first three, I think, are fun and surprising. The final experiment is tedious but teaches you about useful optical devices (quarter-wave plates and half-wave plates); half-wave plates are used in the quantum entanglement experiment, for example. Experiment 1: Microwave Standing Waves Objective: To infer that standing waves are created by the superposition of incident and reflected waves between a microwave receiver and transmitter. Introduction: As students varied the distance between a microwave receiver and transmitter, they recorded the data shown in Figure 1.1. Figure 1.1. Microwave intensity at the receiver as a function of distance between the receiver and the transmitter. (Data taken by N. Cuccia.) Why in the world should the intensity behave like this? It's certainly not a "snapshot" of the traveling wave emitted by the transmitter. How did we derive an equation to fit the data? I'll get you started. Suppose that a (sector of a) spherical wave is emitted by the transmitter. Then, the electric field along the line between the transmitter and the receiver is A E cos(kx t) , (1.1) 1 x where A is a constant, and you probably know what everything else is. A little reflection (ha ha!) will convince you that the wave reflected off the receiver is rA E cos[k(2L x) t] , (1.2) 2 2L x where r is the amplitude reflection coefficient, and L is the distance between the transmitter and the receiver. What's the significance of (2L-x)? It's the total distance traveled by the wave. -
B.Sc.( Srmester-3) Subject: Physics Course: US03CPHY01 Title: Optics
B.Sc.( Srmester-3) Subject: Physics Course: US03CPHY01 Title: Optics UNIT – III Polarization Introduction:- • Interference and diffraction phenomena proved that light is a wave motion. These phenomena are used to find wavelength of light. However, they do not give any indication regarding the character of waves. • Maxwell developed electromagnetic theory and suggested that light-waves are electromagnetic waves. Electromagnetic waves are transverse waves, so it is obvious that light waves are also transverse waves. • Longitudinal waves are waves in which particles of medium oscillate along the direction of propagation of wave (e.g. sound wave). • Transverse waves are waves in which particles of medium oscillate perpendicular to the direction of propagation of wave. (e.g. Electromagnetic waves.) • Polarization is possible in transverse wave. • Unpolarized Light is the light is which the planes of vibration are symmetrically distributed about the propagation direction of the wave. • Plane Polarized light is a wave in which the electric vector is everywhere confined to a single plane. • A linearly polarized light wave is a wave in which the electric vector oscillates in a given constant orientation. Production of Linearly Polarized Light: Linearly polarized light may be produced from unpolarized light using following optical phenomena. (i) Reflection (ii) Refraction (iii) Scattering (iv) Selective absorption (v) Double reflection. Polarized light has many important applications in industry and engineering. One of the most important applications is in liquid crystal displays (LCDs) which are widely used in wristwatches, calculators, T.V. Screens etc. An understanding of polarization is essential for understanding the propagation of electromagnetic waves guided through wave-guides and optical fibers. -
Chapter 8 Polarization
Phys 322 Chapter 8 Lecture 22 Polarization Reminder: Exam 2, October 22nd (see webpage) Dichroism = selective absorption of light of certain polarization Linear dichroism - selective absorption of one of the two P-state (linear) orthogonal polarizations Circular dichroism - selective absorption of L-state or R-state circular polarizations Using dichroic materials one can build a polarizer Dichroic crystals Anisotropic crystal structure: one polarization is absorbed more than the other Example: tourmaline Elastic constants for electrons may be different along two axes Polaroid 1928: dichroic sheet polarizer, J-sheet long tiny crystals of herapathite aligned in the plastic sheet Edwin Land 1938: H-sheet 1909-1991 Attach Iodine molecules to polymer molecules - molecular size iodine wires Presently produced: HN-38, HN-32, HN-22 Birefringence Elastic constants for electrons may be different along axes Resonance frequencies will be different for light polarized Refraction index depends on along different axes polarization: birefringence Dichroic crystal - absorbs one of the orthogonal P-states, transmits the other Optic axis of a crystal: the direction of linear polarization along which the resonance is different from the other two axes (assuming them equal) Calcite (CaCO3) Ca C O Image doubles Ordinary rays (o-rays) - unbent Extraordinary rays (e-rays) - bend Calcite (CaCO3) emerging rays are orthogonaly polarized Principal plane - any plane that contains optical axis Principal section - principal plane that is normal to one of the cleavage