Coulomb Interaction Effects in Semiconductor Heterostructures with Spin-Orbit Interaction

In this thesis we analyze two different situations where the interplay between the spin-orbit coupling (SOI) of the Rashba and Dresselhaus type, linear in the elec-tron momentum, and the Coulomb interaction generates a specific macroscopic phe-nomenology that can be experimentally observed. In the first problem, we investigate the Friedel oscillations that can be sustained in in the presence of the Coulomb repul-sion in a two-dimensional lateral superlattice with SOI and analyze the dependence on several system parameters. Then, we are concerned with the properties of a single quantum well in the special regime where the coupling strengths of the Rashba and Dresselhaus interactions are equal. Starting from general total-energy considerations, we demonstrate that the SU(2) spin-rotation symmetry and the resulting persistent helical state (PHS) predicted to occur are not in fact realized; the actual spin order being that of an itinerant antiferromagnet (IAF). We obtain numerical results that describe the temperature evolution of the order parameter in the IAF state and deter-mine the critical temperature of the transition to the paramagnetic order. Transport in this state is modeled by using the solutions of a Boltzmann equation obtained within the relaxation time approximation. Numerical estimates performed for realistic GaAs and InAs samples indicate that at low temperatures, the amplitude of the spin-Seebeck coefficient can be increased by scattering on magnetic impurities