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.