Controlling hole spin dynamics in two-dimensional hole systems at low temperatures

With the recent discovery of very long hole spin decoherence times in GaAs/AlGaAs heterostructures of more than 70 ns\udin two-dimensional hole systems, using the hole spin as a viable alternative to electron spins in spintronic applications seems\udpossible. Furthermore, as the hyperfine interaction with the nuclear spins is likely to be the limiting factor for electron spin\udlifetimes in zero dimensions, holes with their suppressed Fermi contact hyperfine interaction due to their p-like nature should\udbe able to show even longer lifetimes than electrons. For spintronic applications, electric-field control of hole spin dynamics\udis desirable.\udHere, we report on time-resolved Kerr rotation and resonant spin amplification measurements on a two-dimensional hole\udsystem in a p-doped GaAs/AlGaAs heterostructure. Via a semitransparent gate, we tune the charge density within the sample.\udWe are able to observe a change in the hole g factor, as well as in the hole spin dephasing time at high magnetic fields