##
Doctoral thesis defense

Transport Phenomena in Quantum Wells and Wires
in Presence of Disorder and Interactions

### Valeria Vettchinkina

Mathematical Physics

**Tuesday, 29 May 2012, 13:30**

Lecture Hall F

**Abstract**:

Present-day electronics employ circuits of smaller and smaller
dimensions, and today the length scales are so small that the laws of
physics which rule micro-cosmos, quantum mechanics, become directly
important. This thesis reports on theoretical work on electron
transport in different nanostructures. We have studied semiconductor
quantum wells, layered materials where each layer can be only a few
atomic layers thick, and transport in thin atomic wires. The layered
materials have been studied semi-classically by means the so-called
Bolzmann equation and Monte-Carlo techniques. The works on layered
materials focused on effects of resonant scattering mechanisms on the
electron transport and the feasibility to use semiconductor superlattices
for generating terahertz (THz)radiation. The quantum wires
were modeled by 1D Hubbard chains connected to semi-infinite leads and
were treated fully quantum-mechanically via the time-dependent densityfunctional
theory (TDDFT). Our TDDFT treatment appears to be able to
capture complex features due to competition between correlation and
disorder. The merits of the coherent-potential approximation are also
analyzed for contacted chains.