Oblique Hanle measurements of InAs/GaAs quantum dot spin-light emitting diodes
Itskos, G × Harbord, E Clowes, SK Clarke, E Cohen, LF Murray, R Van Dorpe, Pol Van Roy, W #
Amer inst physics
Applied Physics Letters vol:88 issue:2
We report on studies of electrical spin injection from ferromagnetic Fe contacts into semiconductor light emitting diodes containing single layers of InAs/GaAs self-assembled quantum dots (QDs). An oblique magnetic field is used to manipulate the spin of the injected electrons in the semiconductor. This approach allows us to measure the injected steady-state spin polarization in the QDs, P-spin as well as estimate the spin losses in the QD spin detector. After subtraction of magneto-optical effects not related to spin injection, we measured a P-spin of 7.5% at 15 K and estimated an injected spin polarization before QD recombination of around 20%.