abstract

• We investigate the influence of the MgO growth process on the bias dependence of the electrical spin injection from a Co-Fe-B/MgO spin injector into a GaAs-based light-emitting diode (spin LED). With this aim, textured MgO tunnel barriers are fabricated either by sputtering or molecular-beam-epitaxy (MBE) methods. For the given growth parameters used for the two techniques, we observe that the circular polarization of the electroluminescence emitted by spin LEDs is rather stable as a function of the injected current or applied bias for the samples with sputtered tunnel barriers, whereas the corresponding circular polarization decreases abruptly for tunnel barriers grown by MBE. We attribute these different behaviors to the different kinetic energies of the injected carriers linked to differing amplitudes of the parasitic hole current flowing from GaAs to Co-Fe-B in both cases. © 2017 American Physical Society.

authors

• Amand T.
• Barate P.
• Cadiz F.
• Devaux X.
• Frougier J.
• Garandel T.
• George J.M.
• Han X.F.
• Hehn M.
• Jaffrès H.
• Liang S.
• Lu Y.
• Lépine B.
• Mangin S.
• Marie X.
• Renucci P.
• Schieffer P.
• Tao B.
• Tricot S.
• Vidal Borbolla Miguel Angel
• Wang Z.G.
• Xu B.
• Zhang T.T.

publication date

• 2017-01-01

published in

• Physical Review Applied  Journal

keywords

• Circular polarization; Electroluminescence; Gallium arsenide; III-V semiconductors; Iron compounds; Kinetic energy; Light emitting diodes; Magnesia; Molecular beam epitaxy; Semiconducting gallium; Textures; Bias dependence; Electrical spin injection; Growth parameters; Growth process; Hole current; Injected carriers; Injected current; Tunnel barrier; Cobalt compounds

Digital Object Identifier (DOI)

• 10.1103/PhysRevApplied.8.054027

start page

end page

volume

• 8

issue

• 5