Electric field control photo-induced Hall currents in semiconductors
Author(s)
Miah, M Idrish
Griffith University Author(s)
Year published
2008
Metadata
Show full item recordAbstract
We generate spin-polarized carrier populations in GaAs and low temperature-grown GaAs (LT-GaAs) by circularly polarized optical beams and pull them by external electric fields to create spin-polarized currents. In the presence of the optically generated spin currents, anomalous Hall currents with an enhancement with increasing doping are observed and found to be almost steady in moderate electric fields up to not, vert, similar120 mV 孭1, indicating that photo-induced spin orientation of electrons is preserved in these systems. However, a field not, vert, similar300 mV 孭1 completely destroys the electron spin polarization due ...
View more >We generate spin-polarized carrier populations in GaAs and low temperature-grown GaAs (LT-GaAs) by circularly polarized optical beams and pull them by external electric fields to create spin-polarized currents. In the presence of the optically generated spin currents, anomalous Hall currents with an enhancement with increasing doping are observed and found to be almost steady in moderate electric fields up to not, vert, similar120 mV 孭1, indicating that photo-induced spin orientation of electrons is preserved in these systems. However, a field not, vert, similar300 mV 孭1 completely destroys the electron spin polarization due to an increase of the D'yakonov-Perel' spin precession frequency of the hot electrons. This suggests that high field carrier transport conditions might not be suitable for spin-based technology with GaAs and LT-GaAs. It is also demonstrated that the presence of the excess arsenic sites in LT-GaAs might not affect the spin relaxation by Bir-Aronov-Pikus mechanism owing to a large number of electrons in n-doped materials.
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View more >We generate spin-polarized carrier populations in GaAs and low temperature-grown GaAs (LT-GaAs) by circularly polarized optical beams and pull them by external electric fields to create spin-polarized currents. In the presence of the optically generated spin currents, anomalous Hall currents with an enhancement with increasing doping are observed and found to be almost steady in moderate electric fields up to not, vert, similar120 mV 孭1, indicating that photo-induced spin orientation of electrons is preserved in these systems. However, a field not, vert, similar300 mV 孭1 completely destroys the electron spin polarization due to an increase of the D'yakonov-Perel' spin precession frequency of the hot electrons. This suggests that high field carrier transport conditions might not be suitable for spin-based technology with GaAs and LT-GaAs. It is also demonstrated that the presence of the excess arsenic sites in LT-GaAs might not affect the spin relaxation by Bir-Aronov-Pikus mechanism owing to a large number of electrons in n-doped materials.
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Journal Title
Materials Chemistry and Physics
Volume
111
Issue
2-3
Publisher URI
Subject
Macromolecular and materials chemistry
Chemical engineering not elsewhere classified
Materials engineering
Nanotechnology