Spin-current in a Magnetic Semiconductor Tunnel Junction: Effect of External Bias Voltage
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DOI:
https://doi.org/10.15625/0868-3166/17046Keywords:
spin-orbit interaction, III-V semiconductor, magnetic tunnel junction, spin-current, multi-band transport, transfer matrix, k.p methodAbstract
This paper investigates spin-current transport in a GaMnAs/GaAs/GaMnAs magnetic semiconductor tunnel junctions under applied bias voltages. The 30-band k.p approach is used to describe the materials within the heterostructure, incorporating both spin-orbit and exchange interactions. We use the transfer-matrix formalism to derive numerical solutions for the wave functions. At specific bias values, we calculate the polarization of the spin-current component along the z direction of the structure. We show oscillations of the two spin-current components perpendicular to the magnetization with equal polarization amplitude and characteristic period. The polarization amplitude varies around 10%, reflecting the typical polarization in such type of material. The oscillation period - which relates to the Larmor frequency for spin precession - increases with the bias voltage values.
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Vietnam Academy of Science and Technology
Grant numbers ICP.2021.12
