Condensed Matter Physics Study Guide Graded A+

Amorphous material types {Ans: Glasses, liquids, thin films, metallic glasses, ion-damaged materials Generally liquids, where atomic kinetic energies are too high to remain bound in a crystal}Reciprocal space lattice {Ans: Fourier transform of real space lattice}Pairwise potential {Ans: Sum of Coulomb repulsion and nearest neighbour repulsion}Sapphire vs Ruby {Ans: Same structure, same bandgap so optical absorption curves the same Different natural impurities cause the difference in colour as they result in different transmission curves}Effective mass and curvature {Ans: Sharper curve/higher curvature => lower effective mass Smoother curve/lower curvature => higher effective mass}Conduction in nearly filled bands (holes) {Ans: Consider the behaviour of the few empty states (holes) rather than all the filled e- states Empty states near top of valence band behave as positively charged particles with positive effective mass}