Crystalline Structure. Lattice. Basis. +. Solid State Physics. Quantum mechanics has played a very important role in the development of our understanding of the electronic and physical nature of solid materials.
Face centred cubic lattice.
Simple cubic lattice.
Body centred cubic lattice.
For infinite square well:
1 E < Ef
0 E > Ef
i.e. all states are occupied up to the Fermi level (probability f(E) =1)
when the atoms are far apart, split into two states of different energy in keeping with the Pauli exclusion principle. The same happens to the 2s state as shown in figure (a).
Partially filled band
Sodium energy bands
Light Emitting Diodes (LED)
Photodiodes and Solar Cells
Small base current is used to control large collector current
Arrow shows direction of conventional current flow during normal operation
vcc (supply voltage)
Simple circuit illustrating transistor action
(e.g.) For VCC = 10V, hFE = 200 (typical), RL =4.7kW
Vout =10V if IB = 0A
Vout = 0V if IB ~11mA