2018/2019

2018/2019

DM270

FIS/03 (MATERIAL PHYSICS)

DEPARTMENT OF PHYSICS

Fisica teorica

1°

2nd semester (04/03/2019 - 14/06/2019)

6

48 lesson hours

Italian

ORAL TEST

GERACE DARIO (titolare) - 6 ECTS

This course deals with interdisciplinary topics in either theoretical or condensed matter physics. To be fully appreciated and most usefully attended, it requires the knowledge of basic notions of electromagnetism, optics, quantum physics, and solid-state physics, at the level of bachelor degree in Physics. As such, the course is mainly devoted to Master students in Physics, and it can eventually be attended by PhD students as well.
The course is held in the second semester, with attendance of ‘Solid State Physics I’ as a valuable prerequisite.

The course aims at delivering basic conceptual knowledge about the physics of semiconductor nanostructures for the confinement of electrons and holes. Specific systems to be treated include low-dimensional systems obtained by exploiting modern epitaxial growth techniques. Moreover, the course aims at giving a broad overview about the recent applications of nanostructured devices, such as lasers and light emitting diodes, or single-electron transistors. The targeted objectives can be summarized as follows:
1 – learning the main semiconductor materials growth and nanofabrication technologies; acquiring basic theoretical knowledge of the effects of reduced dimensionality on optical and transport properties; understanding of the main theoretical and experimental tools characterizing the physics of semiconductor nanostructures;
2 – applications of the concepts acquired, e.g. to the problem solving on targeted problems in the physics of nanostructures; comparing the different nanostructures based on their qualitative optical and transport behaviors;
3 – being able to read, learn and communicate the results of recent scientific papers.
At the end of the course, a ‘suggested reading’ session is devoted to students’ presentations about one or more recent research papers, chosen among a few proposed and dealing with the recent developments in the physics of nanostructures.

The course deals with the physics and applications of semiconductor nanostructures, i.e., low-dimensional systems giving rise to quantum confinement effects for electrons and holes in one, two or three dimensions. The following subjects will be treated:
- First-principles calculations, band discontinuities.
- Heterostructures, envelope-function method.
- Two-dimensional systems: quantum wells, superlattices, hetero-interfaces.
- Optical properties. Absorption and emission, interband and intersubband transitions in quantum wells, semiconductor laser. Confined excitons and polaritons.
- Trasport properties. Tunnelling and negative differential resistance, tunnelling diode, resonant tunnelling in double-barrier structures. Effects of electric and magnetic fields. Quantum Hall effect, integer and fractional.
- One- and zero-dimensional systems: quantum wires and quantum dots, electronic levels, transport and optical properties, correlation effects.
- Photonic confinement (semiconductor microcavities and photonic crystals, short mention). Semiconductor cavity QED and Jaynes Cummings model.

Lectures are given through PowerPoint presentations and blackboard explanations. The PowerPoint slides will facilitate the comprehension of the main concepts thanks to the projection of exemplifying pictures, high-resolution images, plots of theoretical and experimental data, while blackboard demonstrations and derivations will be needed to pause on topics that require more attention from the student. Theoretical aspects will be mainly treated through blackboard lectures. While no exercise classes will be given, a few examples on how to deal with problems and exercises will be presented during the regular lectures. Occasionally, the regular course lectures could be complemented by seminars or invited lectures given by distinguished and highly qualified professors and researchers.

L.C. Andreani, Lecture notes (1998/1999).
P.Y. Yu, M. Cardona, Fundamentals of Semiconductors: Physics and Material Properties, 3rd edition (Springer, 2005). ).
J.H. Davies, The Physics of Low-dimensional Semiconductors: An Introduction (Cambridge University Press, 1998).

The students acquisition of knowledge objectives will be verified through and oral examination. The oral colloquium will be focused on at least three of the topics treated during the course, and the student will be allowed to begin discussing one at his own choice. Then, the examining board will continue with specific and targeted questions, with an overall duration of the exam being between 45 and 60 minutes, usually. The final mark will be the result of the evaluations of the answers to the single topics.
In evaluating the students knowledge and understanding, it is recommended to focus on physical aspects (qualitative trends, figures, methods for measuring various physical properties) rather than on a detailed study of mathematical derivations.

The students acquisition of knowledge objectives will be verified through and oral examination. The oral colloquium will be focused on at least three of the topics treated during the course, and the student will be allowed to begin discussing one at his own choice. Then, the examining board will continue with specific and targeted questions, with an overall duration of the exam being between 45 and 60 minutes, usually. The final mark will be the result of the evaluations of the answers to the single topics.
In evaluating the students knowledge and understanding, it is recommended to focus on physical aspects (qualitative trends, figures, methods for measuring various physical properties) rather than on a detailed study of mathematical derivations.