Large and robust electrical spin injection into GaAs at zero magnetic field using an ultrathin CoFeB/MgO injector

Binary information encoded within the spin of carriers can be transferred into corresponding right- or left-handed circularly polarized photons emitted from an active semiconductor medium via carrier-photon angular momentum conversion. In order to attain maximized spin injection at out-of-plane magn...

Full description

Saved in:
Bibliographic Details
Published in:Physical review. B, Condensed matter and materials physics Condensed matter and materials physics, 2014-08, Vol.90 (8), p.505-505, Article 085310
Main Authors: Liang, S. H., Zhang, T. T., Barate, P., Frougier, J., Vidal, M., Renucci, P., Xu, B., Jaffrès, H., George, J.-M., Devaux, X., Hehn, M., Marie, X., Mangin, S., Yang, H. X., Hallal, A., Chshiev, M., Amand, T., Liu, H. F., Liu, D. P., Han, X. F., Wang, Z. G., Lu, Y.
Format: Article
Language:English
Subjects:
Carriers
Circular polarization
Condensed Matter
Emittance
Injectors
Magnetic fields
Materials Science
Optical properties
Physics
Remanence
Semiconductors
Citations: Items that this one cites
Items that cite this one
Online Access:Get full text
Tags: Add Tag
No Tags, Be the first to tag this record!
Description
Summary:Binary information encoded within the spin of carriers can be transferred into corresponding right- or left-handed circularly polarized photons emitted from an active semiconductor medium via carrier-photon angular momentum conversion. In order to attain maximized spin injection at out-of-plane magnetic remanence, a number of material systems have been explored as possible solid-state spin injectors. However, the circular polarization (P sub(C)) of emitted light was still limited at 3-4% at remanence. Here, we demonstrate a sizable electroluminescence circular polarization from a III-V-based spin light-emitting diode at zero magnetic field with a perpendicular spin injector consisting of an ultrathin CoFeB ferromagnetic layer (1.2 nm) grown on a MgO tunnel barrier (2.5 nm). The maximum value of P sub(C) measured at zero field is as large as 20% at 25 K and still 8% at 300 K. These types of ultrathin perpendicular spin injectors are of great interest (i) to realize the electrical switching of the magnetization of the injector layer owing to the advanced spin-transfer torque properties of the CoFeB layer and (ii) to be directly embedded in optical cavities for spin lasers due to their very low optical absorption loss.
ISSN:1098-0121
1550-235X
DOI:10.1103/PhysRevB.90.085310