About Physics 156.

My office is ISB 243.
The best way to contact me is by email at:
zacksc at gmail.com
Please use just this email (not any other emails you may have for me).

Our final, assuming I am reading the UCSC schedule correctly, is on Wednesday, June 11, 2014. That is scheduled by UCSC and set in stone. Other things are not completely certain at this time, but I expect to have a midterm close to the middle of the quarter.

Our midterm will take one full class.  We'll see if we want to have quizzes or not.

Homework will be due more often on Tuesday than Thursday, but both are possible. Expect a lot of homework. Please keep all your returned HW in a homework portfolio to be turned in at the final.

This Blog will play a key role in the class. Please check it frequently and please participate in the discussions here. This is the place to ask questions.

Book: For people who like to have a book, Streetman, 6th or any edition, is probably pretty good. I think it is available for about $25 on ABE books and other sites, but it is expensive on amazon for some reason.

We will start with and examination of energy bands in crystals. A crystal is a system made of atoms in a perfect periodic arrangement. Energy bands refer to the crystal energy eigenstates (wave-functions) that arise when we solve the problem of a single electron in a spatially periodic potential. This is analogous to the manner in which the periodic table provides a starting point for understanding the electron configuration of atoms. These approaches emphasize symmetry.  That is spherical symmetry for the case of an atom, hence the s, p, d, f nomenclature, which comes from grouping energy eigenstates according to their symmetry (technically the representation of the rotation group to which they belong, but never mind that now). For the crystal it is a sort of remnant spherical symmetry, hence the s, p, d and f origins tend to survive, along with a partial translational symmetry (e.g., invariance under translation by "a"). (The translational symmetries can get more complex in 2 and 3 dimensions. Graphene is an interesting example of a 2D crystal structure if you are curious.) Crystals can be either semiconductors (Si, GaAs) or metals (Au, Fe, Pb). (An intrinsic semiconductor is essentially an insulator with a small energy separation between bands.) Bands are the natural starting point to understanding semiconductors and semiconductor devices, metallic behavior, magnetism, superconductivity and pretty much anything else that is based on the quantum behavior of electrons in a periodic potential.

So my plan is to start with bands. (The approach we are taking is called "tight-binding" (bad name) or, more descriptively, linear combination of atomic orbitals (LCAO). Reading about "free electron bands" may confuse you; that is a different approach that is not helpful for us and less reflective of the nature of anything real.) Then after "bands" I am thinking that we will transition quickly to understanding doped semi-conductors and then some semi-conductor devices such as p-n junctions and FETs (MOSFET for one).  Maybe also how electrons can be confined to the surface of GaAs and how a 2D metal forms there, isolating single electrons and other stuff. I am curious to learn about your level of interest in various topics...

If you want to read about something I would recommend reading about doped semiconductors, chemical potential, p-n junctions and FETs and other semi-conductor physics and device stuff.