OBIETTIVI FORMATIVI

Achieving a thorough understanding of the properties solids at the microscopic level. Students will master the concepts of crystal lattice, lattice dynamics, electronic band structure, dielectric response and electronic excitations, magnetic properties and excitations, as well as the origin of metallic, semiconductor and insulator behavior

PROGRAMMA/CONTENUTO

Review of wave phenomena, plane waves, normal modes, Fourier analysis, wavepackets, Maxwell equations, Schrodinger equation and atomic orbitals.

Introduction to the periodic structure of solids, direct lattice, translational and point symmetries, Bravais lattices, lattice with a basis, Wigner-Seitz cell, types of chemical bonds, structure of elements and simple compounds. Interference and diffraction of waves, Laue and Bragg condition, reciprocal lattice, Brillouin zones. Brief introduction on X-ray diffraction. Vibrational dynamics of solids, monoatomic and diatomic chains, acoustic and optical branches, quantization of vibrations and phonons, density of states, Einstein and Debye models, specific heat, brief analysis of anharmonicity to treat thermal expansion. Brief introduction on inelastic neutron scattering. Free electron models: classical Drude model, electrical conduction, Hall effect, thermal properties. Quantum statistics of identical particles, bosons and fermions, Sommerfeld model, Fermi sphere, Fermi energy and chemical potential, Sommerfeld expansion and correction to the Fermi energy. Failure of the classical description. Independent electron approximation in a periodic potential, Bloch theorem and band theory. Weak periodic potential and nearly free electron approximation, electronic structure and Fermi surface. Tight Binding approximation. Valence and conduction bands, electron velocity, electrical properties of full and partially filled bands, concept of holes. Metals, semiconductors, and insulators.

TESTI/BIBLIOGRAFIA

“Introduction to Solid State Physics”, Charles Kittel, 8th ed., John Wiley & Sons, 2005.

“Solid state physics”, N. W. Ashcroft, N. D. Mermin, Harcourt College Publishers, 1976.