1、Chapter 1 Brief introduction to Quantum Physics Thus,c). When P has a finite value, The energy of electrons be characterized by a series of allowed and forbidden regions.,A typical energy versus k plot,The energy as a function of k. The discontinuities occur at k = n/a, n = 1, 2, 3, .,One-dimensiona

2、l energy band diagram in a reduced zone scheme.,The KronigPenney model is a simple, analytically solvable model that visualizes the effect of the periodic potential on the electrons, and the formation of a band structure.,Example 5. Wave equation of electron in a general periodic potential(電子在周期勢場中的

3、波動方程),The solution in a general periodic zone scheme. The free electron curve is drawn for comparison.,Occupied states and band structures giving (a) an insulator, (b) a metal,Band structure of (a) Si and (b) Ge,Band structure of GaN and CuAlO2,Energy Band Theory,The energy band structure of a solid

4、 can be constructed by solving the Schrdinger equation for electrons in a crystalline solid which contains a large number of interacting electrons and atoms.,Complexity: many-body problem - motion of atomic nuclei - many electrons,Many method is used to solve many-body problem: Tight-binding approximation, The cellular (Wigner-Seitz) method, The augmented-plane wave (APW) method