Infrared radiation induced gyrotropic photocurrents in semiconductor nanostructures

摘要

This thesis deals with an advanced experimental investigation of infrared radiation induced gyrotropic photocurrents in semiconductor nanostructures. These provide an access to non-equilibrium processes in low-dimensional materials like quantum wells allowing especially studies of spin and orbital properties of carriers. Even though a noticeable progress in both the basic research and utilisation of the gyrotropic currents has been achieved, their complete understanding is still a challenge. The conducted measurements improve the knowledge by revealing a number of new phenomena. Among them are a first experimental observation of circular photon drag effect demonstrating a simultaneous transfer of photon linear and angular momenta to carriers and a detection of a nonlinear magneto-gyrotropic photocurrent. The latter effect coheres with the heavy-hole type of the lowest conduction band in HgTe quantum wells allowing, for instance, determination of the quantum spin Hall insulator state.