Resonant response of a system to external electro-magnetic perturbations is in the heart of the condensed matter physics and most of its applications in electronics and optoelectronics. External fields can strongly modify spectral properties (Hall effect, superlattices), lead to nonequilibrium distribution of carriers (laser physics), and cause instabilities yielding qualitatively new transport behavior (Gunn effect, electrical instabilities in superlattices, light generation, zero resistance states). The aim of the project is to develop theory for the transport and optical properties of emergent nanostructures where the above effects play a crucial role. In particular, the project addresses (A) ultra-high-mobility two-dimensional electron gas in quantizing magnetic field, driven by strong dc and microwave fields (recent experiments on photoconductivity of quantum Hall systems discovered novel types of magnetooscillations and zero resistance states, which attracted a great deal of interest), (B) quantum cascade structures consisting of a regular array of tunnel-coupled quantum dots (potentially, very efficient source of coherent radiation in THz and far-infrared range of frequencies).
