Enhancement of magneto-photogalvanic effect in periodic GaAs dot arrays by p-n junctions coupling

To control thesemiconductor device under lowmagnetic field is still a great challenge forsemiconductormagnetoelectronics. In this work, we report the observation of the magneto-photogalvaniceffect in periodicGaAs dot arrays. With an increase inmagnetic field from 0 to 1500  Oe, the photovoltage increases linearly for a wide temperature range from 80 to 430 K. Compared withGaAs without the dot arrays, periodicGaAs dot arrays have a hundredfold increase of the magnetic-field-modulated photovoltage at room temperature. By changing themagnetic field orientation, the angular dependence of photovoltage reveals that the magneto-photogalvaniceffect stems from the Hall electric field caused by optical current, and the enhancement of magneto-photogalvaniceffect is attributed to thep-n junction coupling betweenGaAs dots. When the coupling between theGaAs dots is broken at the high temperatures, i.e.,T = 430 K, we demonstrate that the enhancementeffect disappears as expected. Our results not only illustrate the magnetic control of energy flow in light harvest, but also provide an applicable way forsemiconductormagnetoelectronics by utilizingp-n junction coupling.

Source: Applied Physics Letters - December 5, 2016 Category: Physics Authors: J. K. Zhou, T. Wang, W. Wang, S. W. Chen, Y. Cao, H. P. Liu, M. S. Si, C. X. Gao, D. Z. Yang and D. S. Xue Source Type: research