Department of Physics 2012-2013 Spring/Summer Zhejiang University

SolidSolid StateState PhysicsPhysics II Lecture One

万 歆 Outline

● Course outline

● Course arrangement

● Office hour, TA

● Team project

● A material introduction to selective local groups

● Semiconductors: Si, GaAs, Li(Zn, Mn)As

● Heavy fermion materials: CeCu Si , CeRhIn 2 2 5

● Superconductors: Gd Th FeAsO, (Tl,K)Fe Se , La Sr CuO , Sr RuO 1-x x x 2 2-x x 4 2 4

● More is different and P.W. Anderson

● Periodic table

● Introduction to metals

2 Diluted Magnetic Semiconductor Li(Zn,Mn)As

Fanlong Ning （宁凡龙） and his collaborators (2011)

3 Heavy Fermion Superconductor CeCu Si 2 2

H.Q. Yuan ( 袁辉球 ) et al., Science 302, 2104 (2003) 4 Superconductivity up to 56 K in Gd Th FeAsO 1-x x

Guanghan Cao （曹光旱） and Zhu'an Xu （许祝安） groups Europhys. Lett. 83, 67006 (2008)

5 Topological Superconductor Sr RuO 2 4

Jang et al., Science (2011)

6 Reductionism

● Reductionism is an approach to understanding the nature of complex things by reducing them to the interactions of their parts, or to simpler or more fundamental things.

● Both Kepler's laws of the motion of the planets and Galileo's theories of motion, e.g., worked out for terrestrial objects are reducible to Newtonian theories of mechanics. The reduction is considered to be beneficial because Newtonian mechanics is a more general theory— i.e., it explains more events than Galileo's or Kepler's.

● Physicists reduce matter first to molecules, then to atoms, then to nuclei and electrons, and so on, the goal being always to reduce complexity to simplicity. The extraordinary success of that approach is based on the concept of an isolated system.

● But no real physical or biological system is truly isolated, physically or historically. Indeed, the laws of behavior in complex systems emerge from, but are to a large degree independent of, the underlying low-level physics. 7 Emergence of Order, Pattern, and Properties

The Nobel Prize in Physics 1977 was awarded jointly to Philip Warren Anderson, Sir Nevill Francis Mott and John Hasbrouck van Vleck "for their fundamental theoretical investigations of the electronic structure of magnetic 8 and disordered systems". Philip W. Anderson

● P. W. Anderson was educated at Harvard, with a brief hiatus (1943-45) for war work. From 1949-1984 he was associated with the AT&T Bell Laboratories, but also held a number of temporary or part-time academic positions:

● 1953-54 Fulbright Scholar, University of Tokyo

● 1961-62 Overseas Fellow, Churchill College, Cambridge

● 1967-75 Visiting Professor, Cambridge University

● 1975-present Joseph Henry Professor, Princeton University. 1993-94 he spent a year as Eastman Professor, Balliol College, Oxford.

● Awards:

● 1977 Nobel Prize in Physics

● 1982 National Medal of Sciences

● Heinemann Prize (Gottingen Academy), Guthrie Medal (IOP)

9 A Career in Theoretical Physics: Introductory Essay

It was in the winter of 1966-7 that I first tried to express my philosophy of what was important in science – or at least, of what was important that was possible for me. I has been invited to spend a month in the pleasant climate of La Jolla as the Regents' lecturer at the UCSD, visiting a department staffed by many of my old friends from Bell Labs, such as Bernd Matthias, Harry Suhl, and George Feher, who had been recruited by Walter Kohn, who was also by courtesy a Bell alumnus. One of the lecturers I gave was called “More is Different”. The original version, now lost, went over with the audience like a lead balloon, at least according to that portion of the audience most closely related to me. But a cleaned up version, which was published in Science in 1972, has been surprisingly influential. I have chosen to reprint it, out of chronological order, as an additional introduction to this collection. – P. W. Anderson, Oxford, Dec. 2, 1993

10 “Hot” Elements in Recent Literature

11 Groups of Like Elements

● Alkali metals – The metals of group 1: Li, Na, K, Rb, Cs, Fr.

● Alkaline earth metals – The metals of group 2: Be, Mg, Ca, Sr, Ba, Ra.

● Pnictogens – The elements of group 15: N, P, As, Sb, Bi.

● Chalcogens – The elements of group 16: O, S, Se, Te, Po.

● Halogens – The elements of group 17: F, Cl, Br, I, At.

● Noble gases – The elements of group 18: He, Ne, Ar, Kr, Xe, Rn.

● Lanthanoids – Elements 57-71: La, Ce, Pr, Nd, Pm, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb, Lu.

● Actinoids – Elements 89-103: Ac, Th, Pa, U, Np, Pu, Am, Cm, Bk, Cf, Es, Fm, Md, No, Lr.

● Rare earth elements – Sc, Y, and the lanthanoids.

● Transition metals – Elements in groups 3 to 12. 12 What makes them different?

13 More metallic? Less metallic?

14 Metals in Periodic Table

15 The Electronic Properties of Metals

● What is a metal, anyway?

● A metal is an element, compound, or alloy that is a good conductor of both electricity and heat.

● Metals are usually malleable, ductile and shiny, that is they reflect most of incident light.

● In a metal, atoms readily lose electrons to form positive ions (cations). Those ions are surrounded by delocalized electrons, which are responsible for the conductivity.

● The solid thus produced is held together by electrostatic interactions between the ions and the electron cloud, which are called metallic bonds.

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