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Current-Induced Spin Photocurrent in GaAs at Room Temperature
Yang Zhang1,2, Yu Liu2, Xiao-Lan Xue1
1School of Materials Science and Physics, China University of Mining and Technology, Xuzhou 221116, China.
Sensors (Basel, Switzerland)
|January 11, 2022
Summary
Circularly polarized photocurrent in p-doped bulk GaAs is linked to spin polarization. This study reveals a new optical method for room-temperature investigation of current-induced spin polarization.
Area of Science:
- Condensed matter physics
- Materials science
- Optoelectronics
Background:
- Current-induced spin polarization is a key phenomenon in semiconductors.
- Understanding spin dynamics in p-doped bulk GaAs is crucial for spintronic applications.
- Previous studies have focused on quantum wells, leaving bulk materials less explored.
Purpose of the Study:
- To investigate the origin of circularly polarized photocurrent in p-doped bulk GaAs.
- To explore the relationship between photocurrent and current-induced spin polarization.
- To establish circularly polarized photocurrent as a viable optical technique for studying spin polarization at room temperature.
Main Methods:
- Experimental observation of photocurrent in p-doped bulk GaAs under varying bias voltage.
- Analysis of the nonlinear dependence of photocurrent on applied bias.
- Characterization of the direction of current-induced spin polarization.
Main Results:
- Circularly polarized photocurrent in p-doped bulk GaAs exhibits nonlinear behavior with applied bias voltage.
- The photocurrent is attributed to current-induced spin polarization.
- The spin polarization direction in (001) grown GaAs lies in-plane, perpendicular to the electric field, mirroring findings in quantum wells.
Conclusions:
- Circularly polarized photocurrent is a direct consequence of current-induced spin polarization in p-doped bulk GaAs.
- The observed spin polarization characteristics are consistent between bulk GaAs and GaAs quantum wells.
- This work presents a novel optical approach for probing spin polarization in semiconductors at room temperature.
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