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Circular polarization in a non-magnetic resonant tunneling device.

ABSTRACT: We have investigated the polarization-resolved photoluminescence (PL) in an asymmetric n-type GaAs/AlAs/GaAlAs resonant tunneling diode under magnetic field parallel to the tunnel current. The quantum well (QW) PL presents strong circular polarization (values up to -70% at 19 T). The optical emission from GaAs contact layers shows evidence of highly spin-polarized two-dimensional electron and hole gases which affects the spin polarization of carriers in the QW. However, the circular polarization degree in the QW also depends on various other parameters, including the g-factors of the different layers, the density of carriers along the structure, and the Zeeman and Rashba effects.

SUBMITTER: Dos Santos LF

PROVIDER: S-EPMC3211145 | biostudies-literature | 2011 Jan

REPOSITORIES: biostudies-literature

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Circular polarization in a non-magnetic resonant tunneling device.

Dos Santos Lara F LF Gobato Yara Galvão YG Teodoro Márcio D MD Lopez-Richard Victor V Marques Gilmar E GE Brasil Maria Jsp MJ Orlita Milan M Kunc Jan J Maude Duncan K DK Henini Mohamed M Airey Robert J RJ

Nanoscale research letters 20110125 1

We have investigated the polarization-resolved photoluminescence (PL) in an asymmetric n-type GaAs/AlAs/GaAlAs resonant tunneling diode under magnetic field parallel to the tunnel current. The quantum well (QW) PL presents strong circular polarization (values up to -70% at 19 T). The optical emission from GaAs contact layers shows evidence of highly spin-polarized two-dimensional electron and hole gases which affects the spin polarization of carriers in the QW. However, the circular polarization ...[more]

PMID: 21711613

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