Generating and mapping spin currents with space and time resolution

Abstract

Spin currents can be generated using selective spin contacts, enabling integration in circuits in which device geometry and parameters of spin can be controlled by electrodes. Devices containing a two-dimensional electron gas, in GaAs/AlGaAs channels defined by lithography and electrostatic electrodes, have an extraordinary variety of spin related phenomena. These structures are typically studied by electrical transport measurements in channels with width of microns using quantum point contacts as injectors and detectors. Moreover, optical measurements of spin have advanced the current understanding of spin relaxation, accumulation and separation through the spin-orbit interaction in a variety of bulk materials and quantum wells. The main objective of the project is to gain new fundamental knowledge about the influence of the currents of spin on the optical properties of materials and the behavior of such currents in terms of the diffusion length , coherence time , and spatial dependence in magnetic fields induced by electric fields through spin-orbit interaction. (AU)