Physics 211B : Problem Set #1
[1] Recall that a quantity F (k) that is conserved between collisions satises
d3k
F (k)
(2 )3
d
F (r ) =
dt
f
t
.
k,coll
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f
t
=
k,coll
f (r , k, t)
,
(k )
where f
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Physics 211B : Solution Set #1
[1] Drude formula Consider a hypothetical monovalent s-band metal with a simple cubic
crystal structure. The valence band dispersion is given by the tight binding result,
(k) = 2t cos(kx a) + cos(ky a) + cos(kz a) .
Compute
Physics 211B : Solution Set #2
[1] Rectangular Barrier Consider a symmetric planar barrier consisting of a layer of
Alx Ga1x As of width 2a imbedded in GaAs. The barrier height V0 is simply the dierence
GaAs .
between conduction band minima Ec at the poin
Physics 211B : Problem Set #2
[1] Consider a disordered tight binding model, for which the Schrdinger equation is
o
t n1 t n+1 + n n = E n ,
where t is the hopping integral and n is the local site energy. Compute the Landauer
resistance R = |r|2 /|t|2 for
Physics 211B : Problem Set #3
[1] Find all the possible multiplets for the ions Co2+ and Sm3+ . Find the ground state
terms using Hunds rules.
[2] Consider the paramagnetic phase of the Hubbard model within the Stoner approximation. Compute the charge sus
Physics 211B : Solution Set #4
[1] Atomic physics Consider an ion with a partially lled shell of angular momentum J ,
and Z additional electrons in lled shells. Show that the ratio of the Curie paramagnetic
susceptibility to the Larmor diamagnetic suscept
Physics 211B : Final Exam
Due 10 am, Wednesday March 17, my oce (5671 Mayer Hall)
[1] Consider a tri-junction connecting three identical one-dimensional leads. The leads are
each connected to reservoirs described by chemical potentials at a xed temperatur
Physics 211B : Problem Set #0
These problems provide a cross section of the sort of exercises I would have assigned had I
taught 211A. Please take a look at all the problems, and turn in problems 1, 4, 6, 8, 9, 11,
13, 15, 17, and 18.
p
[1] Determine the
Phys211 B Homework 4, UCSD, 2009 Winter
Problem 1. Spin wave in ferri-magnets. Ferrimagnets are a two-sublattice system with two different spin-values S a and S b coupled by antiferromagnetic exchange J > 0. For example, the lodestone (Fe3 O4 ) discovered
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