Some idea of what should be the background and which, if needed can be regained during the first 2 weeks, can be gotten from the following topics:
Periodic solids; symmetry; reciprocal lattice; Brillouin zone;
Order and periodicity in matter;
Optical absorption, reflectance, in molecular and non-molecular periodic solids
Insulator/dielectrics, semiconductor, metal
Electrical conductivity/resistivity, capacitance, impedance
Maxwell equations
Schroedinger equation; Particle in the box
Boltzmann statistics, Fermi-Dirac statistics; Fermi level
Photon, phonon, spin
(Electro)chemical potential; Electrical potential
Bandgap; Valence band, Conduction band