84538 - Charge Transport and Optics in Condensed Matter

Academic Year 2022/2023

Learning outcomes

At the end of the course the student will learn the basic aspects of the transport and optical properties of condensed matter. These phenomena will be studied within both a classical approach and a quanto-mechanical one with non-interacting electrons.

Course contents

1. Electronic Transport in crystals. Modelling of electronic transport in crystals. Definition and modelling of the quantities that describe the electronic transport in crystals (current density, conductivity, mobility) from classical towards semiclassical approximation. Non- interacting electrons in perfect crystals, electron-electron interaction and scattering mechanisms. The models include: Drude model, Sommerfeld model, transport of non interacting Bloch electrons, semiclassical theory of electronic transport, effective mass approach, relaxation time approach, Boltzmann equation. Combined thermal - electrical- magnetic effects (Seebeck, Peltier, magnetoresistance). Electron-electron interaction, Hartree and Hartree-Fock approximations. Scattering mechanisms, Matthiessen rule.
2. Optical Properties of Solids. Basic Phenomenological models: description of the optical functions and of their relation with the transport properties, Maxwell Equation in condensed matter, Kramers-Kroning relations. Optical properties of semiconductors: measurement of cyclotronic frequency for the determination of effective mass, absorption spectra of a semiconductor, above and below band gap electronic transitions. Optical properties of insulators, dielectric properties, polarization effects, definition of the optical effective mass, polaron and polaritons, colour centers. Optical properties of metals, plasma frequency, plasmons and surface plasmons. Experimental effects and application of light-matter interaction, Raman and Brillouin spectroscopies.
3. Impurities, Defects and Disorder in solids. Point and extended defects, properties and consequences. Surface effects: surface states, work function definition and measurements, surface -related techniques. Effect of crystal disorder on the transport properties of solids, Mott transition, Urbach tails.

Readings/Bibliography

Neil W. Ashcroft and N. David Mermin, Solid State Physics, Harcourt College Publisher

M Marder, Condensed matter physics, Wiley

M. S. Dresselhaus SOLID STATE PHYSICS PART II, Optical Properties of Solids, on web.mit.edu

The lecture notes will be made available on the web site:

iol.unibo.it

Teaching methods

Lectures. Group discussion on selected topics.

Exercises. Discussion on selected applications.

Assessment methods

Oral exam.

The final exam aims to evaluate the achievement of the learning outcomes. The student must be able to present and discuss the  basic aspects of transport and optical properties of condensed matter. 

The first question will be on one topic selected by the student, the second question will be selected by the teacher.

The evaluation of the exam and the final score will test the capability of the student to critically discuss the selected topics. 

Teaching tools

Slide presentations and review articles will be made available via iol.unibo.it. 

Office hours

See the website of Daniela Cavalcoli