A lateral-type spin-photodiode based on Fe/x-AlOx/p-InGaAs junctions with a refracting-facet side window
arXiv:1802.07393 · doi:10.1063/1.5026511
Abstract
A lateral-type spin-photodiode having a refracting facet on a side edge of the device is proposed and demonstrated at room temperature. The light shed horizontally on the side of the device is refracted and introduced directly into a thin InGaAs active layer under the spin-detecting Fe contact in which spin-polarized carriers are generated and injected into the Fe contact through a crystalline AlOx tunnel barrier. Experiments have been carried out with a circular polarization spectrometry set up, through which helicity-dependent photocurrent component, dI, is obtained with the conversion efficiency F ~ 0.4 %, where F is the ratio between dI and total photocurrent Iph. This value is the highest reported so far for pure lateral-type spin-photodiodes. It is discussed through analysis with a model consisting of drift-diffusion and quantum tunneling equations that a factor that limits the F value is unoccupied spin-polarized density-of-states of Fe in energy region into which spin-polarized electrons in a semiconductor are injected.
arXiv comment27 pages, 8 figures, 1 appendix
References in corpus (8)
- Theory of electrical spin injection: Tunnel contacts as a solution of the conductivity mismatch problem
- Semiconductor Spintronics
- Spin diffusion and injection in semiconductor structures: Electric field effects
- Enhancement of the Spin Accumulation at the Interface Between a Spin-Polarized Tunnel Junction and a Semiconductor
- Pure circular polarization electroluminescence at room temperature with spin-polarized light-emitting diodes
- Focusing of Spin Polarization in Semiconductors by Inhomogeneous Doping
- Imaging charge and spin diffusion of minority carriers in GaAs
- Investigation of helicity-dependent photocurrent at room temperature from a Fe/x-AlOx/p-GaAs Schottky junction with oblique surface illumination