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arXiv · 1311.3569

Generation and control of spin-polarized photocurrents in GaMnAs heterostructures

Anibal T. Bezerra·Leonardo K. Castelano·Marcos H. Degani·Marcelo Z. Maialle·Paulo F. Farinas·Nelson Studart
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Abstract

Photocurrents are calculated for a specially designed GaMnAs semiconductor heterostructure. The results reveal regions in the infrared range of the energy spectrum in which the proposed structure is remarkably spin-selective. For such photon energies, the generated photocurrents are strongly spin-polarized. Application of a relatively small static bias in the growth direction of the structure is predicted to efficiently reverse the spin-polarization for some photon energies. This behavior suggests the possibility of conveniently simple switching mechanisms. The physics underlying the results is studied and understood in terms of the spin-dependent properties emerging from the particular potential profile of the structure.

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Anibal T. Bezerra, Leonardo K. Castelano, Marcos H. Degani, Marcelo Z. Maialle, Paulo F. Farinas, Nelson Studart. 2013-11-14. Generation and control of spin-polarized photocurrents in GaMnAs heterostructures. https://doi.org/10.1063/1.4861656

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