Phys 250.2: Computational Band Theory

In the fall quarter of 1998, Physics 250.2 will be a course on formal and especially computational aspects of band theory. The focus will be on achieving a clear understanding of the band problem, and a good general sense of the various techniques that are used to calculate crystalline energy band structures.

The foundation -- the Hartree-Fock approximation -- and the best formal basis -- density functional theory -- will be covered as well.

The course will be offered in the 1998 fall quarter on Tuesdays and Thursdays from 10:30-11:50 AM in PG 999.

At right is an immodest example of a band structure, immodest because this is a very complex, but very unusual magnetic system.

Structure of the primitive cell of CaV4O9, which constains 28 atoms. CaV4O9 is a magnetic insulator that settles into a spin gap phase at low temperature in which there is not magnet order, yet it is not spin-glass like. It is also called a quantum spin ilquid.

This is the rather complex band structure of the ferromagnetic (ordered, hence fictitious) phase of CaV4O9. This system provides an excellent example of both the considerable success of modern band theory, and or its current limitations.