Physics 481: Condensed Matter Physics  Homework 9
due date: Friday, March 25, 2011 Problem 1: Copper nanowire (20 points) Consider a long thin wire of copper along the zdirection with length L = 1 cm and a square cross section (width a is a few ). Treat
Physics 481: Condensed Matter Physics  Homework 8
due date: March 18, 2011 Problem 1: Damped oscillations (10 points) In a linear chain of lattice spacing a, particles of mass m are connected by nearestneighbor springs of spring constant K. In addition
Physics 481: Condensed Matter Physics  Practice Exam
Problem 1: Fermi pancakes Consider a thin layer of copper, 1 mm wide and 1 mm long along x and y. The layer is a few A thick in zdirection. Treat the layer as a free electron gas, demanding the the wa
Physics 481: Condensed Matter Physics  Homework 2
due date: Friday, Jan 28, 2011
Problem 1: Packing fractions in two and three dimensions (20 points) To find the degree of space filling for a given lattice, first find the distance dmin between nearest ne
Physics 481: Condensed Matter Physics  Homework 3
due date: Friday, Feb 4, 2011
Problem 1: Hcp extinctions (Marder, problem 3.2, 20 points) a) The hexagonal Bravais lattice can be defined by the primitive vectors (a, 0, 0), (a/2, a 3/2, 0) and (0, 0, c).
Physics 481: Condensed Matter Physics  Homework 4
due date: Friday, Feb 11, 2011 Problem 1: Nematic order parameter (15 points) Consider a threedimensional nematic liquid crystal consisting of N rodlike molecules. The nematic order parameter (i.e., a q
Physics 481: Condensed Matter Physics  Homework 5
due date: Friday, Feb 18, 2011 Problem 1: Fibonacci chain (8 points) Determine the ratio between the numbers of A and B elements in Fibonacci chains of generation 2,3,4,5. Calculate the limiting value in
Physics 481: Condensed Matter Physics  Homework 6
due date: Thursday, Feb 25, 2011 Problem 1: Model of a nobel gas crystal (20 points) A simple model of a noble gas crystal consists of a f.c.c. lattice with a LennardJones interaction U (r) = 4 r
6

r
Physics 481: Condensed Matter Physics  Test prep Homework 7
due date: Friday, March 5, 2011 Problem 1: Tetragonal lattice (15 points) A hypothetical monoatomic substance crystallizes in a centered tetragonal structure. The conventional unit cell can desc
Physics 481: Condensed Matter Physics  Homework 10
due date: April 15, 2011 Problem 1: Fermi surfaces in two dimensions (10 points) Consider a twodimensional system of nearly free electrons (weak periodic potential) with a square unit cell (lattice cons
Physics 481: Condensed Matter Physics  Homework 11
due date: April 22, 2011 Problem 1: Microscopic Drude theory (AshcroftMermin 1.1, 20 points + 5 BONUS) A microscopic picture of the Drude theory can be built from the following assumptions: (i) While mo
Physics 481: Condensed Matter Physics  Test prep homework
Problem 1: Tightly bound electrons in 1D (10 points) Consider a onedimensional electron system with lattice constant a in tight binding approximation. The energymomentum relation reads (k) = 2t
Physics 481: Condensed Matter Physics  Midsemester test
Friday, March 4, 2011 Problem 1: Structure determination (70 points) DebyeScherrer Xray diffraction is used to study a powder specimen of a monoatomic substance that is known to crystallize in a c
Physics 481: Condensed Matter Physics  Homework 1
due date: Jan 21, 2011
Problem 1: Honeycomb lattice (10 points, Marder  Problem 1.1 ) The honeycomb lattice can be constructed by starting from the hexagonal Bravais lattice with primitive vectors a1 = a