Physics 223B: Condensed Matter Physics

Lecture Tuesday, Thursday 2:00 - 3:15 PM, Ellison 2816

Instructor: Leon Balents
Email: balents@kitp.ucsb.edu
Phone: 893-6381
Office Hours:

M 2:30-3:30 in KITP 2315

F 3-4pm in KITP 2315

Call or email me to meet at another time.

Teaching Assistant: Lucile Savary
Office Hours:

Tuesday 12-12:30

Wednesday 9-10.

Thursday 9-10:30

Problem sets:

Problem set 1: (pdf) . Due January 20, 2009.
- The solution is here: (pdf)
Problem set 2: (pdf) . Due January 27, 2009.
- Need more honeycomb graph paper? Get it here
Problem set 3: (pdf) . Due February 3, 2009.
Homework: Choose your group and topic for your final project (see bottom of page)
Problem set 4: (pdf) . Due February 17, 2009.
Problem set 5: (pdf) . Due February 25, 2009.

This course is the second of three quarters of introduction to condensed matter physics. This quarter, we will focus on the quantum physics of condensed matter. Almost all of this subject is more specifically the electronic properties of solids (why?). We will begin with a review of the band theory of solids. How much should you know? After this class, I hope you will be able to answer these questions:

What is the Hamiltonian describing a solid?
What is the small dimensionless parameter in this Hamiltonian, and what does it imply?
What sets the melting/sublimation point of solids? The most stable elemental solid is carbon which sublimates at nearly 4000K.
What are the basic properties of and differences between metals and insulators?
What is the Sommerfeld model and what are its basic properties?
How do we describe a periodic solid?
What is the reciprocal lattice, and what is its significance to neutron scattering?
What is Bloch's theorem, and what is a band?
What is the difference between momentum and quasimomentum?
What is quasimomentum, and why is the (first) Brillouin zone useful?
What simple relation does band theory predict between the crystal structure of a periodic solid and its metallicity?
Is the band theory picture of an insulator similar to an atomic one (hint: what about Wannier states?)?
What is the nearly free electron approximation?
What is the tight binding approximation?
What is the semiclassical model of electron dynamics? Why is it usually good in a metal?
How do you measure a Fermi surface?
What is a semiconductor?
Why are semiconductors useful?
in progress

If you already know the answers, great! You can help out those who don't.

Here are some more advanced topics we may cover afterward:

The quantum spin Hall effect
Magnetism: atomic moments, collective order, magnons, itinerant magnetism
Superfluidity: BEC, ODLRO, superflow
Superconductivity: Ginzburg-Landau theory, BCS theory
Some mesoscopics?

Textbook (reference)

Ashcroft and Mermin, "Solid State Physics", is recommended but not required.

Prerequisites:

Basic quantum mechanics, including angular momentum, spin, the hydrogen atom, quantum statistics, and perturbation theory. Some elementary statistical mechanics and electromagnetism is assumed.

Grades

to be determined

Final projects:

Students should form groups of 3-4 students, to prepare final oral presentations on a topic of their choice. Presentations should be approximately 30 minutes long, including questions. The topics should be of experimental relevance, in the general area of quantum condensed matter physics, and accessible to the audience of your fellow students. The topics also must be approved by me! One good source of topics is the Journal Club for Condensed Matter Physics .

Last modified: Mon Jan 07 10:27:27 Pacific Standard Time 2008