Observation of spin polarized transport across a ferromagnet–two-dimensional electron gas interface (invited)

Spin injection at a ferromagnet–semiconductor interface has been demonstrated by convolving the spin-split density of states of carriers in a high mobility InAs quantum well with the spin polarization of conduction electrons in a thin ferromagnetic film. Transport measurements on a diode structure detected a spin-dependent interfacial resistance, with ΔRi/R̄i≈1%. In a different configuration, open circuit voltage experiments measure the spin-dependent shifts in the chemical potential of the carriers in the quantum well. Results of the two techniques are compared over the temperature range 50<T<296 K, demonstrating both spin injection and detection at the ferromagnet–semiconductor interface.