20410020 - COMPLEMENTI DI FISICA DELLA MATERIA CONDENSATA

Give the student an in-depth understanding of the transport properties of solid systems and their response to electromagnetic fields

DE SETA MONICA

teacher profile | teaching materials

Programme

Electronic properties of selected crystals
Reminds on band structure calculation methods. Electronic structure of molecular and ionic solids. Band structure of II-VI, III-V systems and of covalent crystals with diamond structure. Impurity levels in doped semiconductors. Internal energy, pressure and compressibility of an electron gas. Band structures and Fermi surfaces of selected metals.

Transport properties:
The Drude Model. Semiclassical Equations of transport. Boltzmann equation. Relaxation time approximation. Static and dynamic electrical conductivity in metals. Thermoeletrictic power and thermal conductivity. Transport in homogeneous and doped semiconductors. Drift and diffusion currents. Generation and recombination of electron-hole pairs in semiconductors. Continuity equation. Recombination times and diffusion length. Current voltage characteristics of the p-n junction. Metal-semiconductor junction. Electron phonon interaction. Matrix elements and selection rules.

Optical properties of solids
Maxwell Equations in solids. Complex Dielectric Constant. Kramers Kronig Relations. Lorentz Oscillator. Absorption and reflection coefficients.
The Drude theory of the optical properties of metals. Optical properties of semiconductors and insulators. Direct interband transitions and critical points. Optical constants of Ge and Graphite. Absorption from impurity levels. Exciton effects. Indirect phonon-assisted transitions. Two-photon absorption. Raman Scattering. Optical phonon absorption.

Electron gas in magnetic fields
Energy levels and density of states of a free electron gas in a magnetic fields. Orbital magnetic susceptibility and Haas-van Alphen effect. Magneto-resistivity and classical Hall effect. Phenomenology of the quantum Hall effect.

Magnetic properties of matter.
Quantum mechanical treatment of magnetic suscectibility. Pauli paramagnetism. Magnetic suscectibility of closed-shell systems. Permanent magnetic dipoles in atoms and ions with partially filled shells. Paramagnetism of localized magnetic moments. Curie and Van Vleck paramagnetism. Magnetic ordering in crystals. Mean field theory of ferromagnetism: Weiss model. Curie-Weiss law. Critical temperature in ferromagnetic materials. Ferromagnetism, exchange interaction and Heisemberg model. Microscopic origin of the coupling between localized magnetic moments.
Dipolar interaction and magnetic domains.


Core Documentation

Ashcroft-Mermin: "Solid State Physics"
Grosso-Pastori-Parravicini: "Solid State Physics"

Type of delivery of the course

Frontal lessons with calculations on the blackboard. Sometimes in-depth studies on more recent research topics may be presented in a seminar format using slides.

Attendance

Attendance is strongly recommended but is not mandatory

Type of evaluation

final oral examination: typically two questions are asked about different topics in the program. The evaluation takes into account the capacity of: a) analyzing the phenomenon in a broad context b)identifying the salient points that give rise to the phenomenology being described c) to arrive at the result through analytical calculations.