Light-enhanced gating effect at the interface of oxide heterostructure

Neha Wadehra, Ruchi Tomar, Yuichi Yokoyama, Akira Yasui, E. Ikenaga, Hiroki Wadati, D. Maryenko, Suvankar Chakraverty

Abstract

Abstract In semiconducting materials, electrostatic gating and light illumination are widely used stimuli to tune the electronic properties of the system. Here, we show a significant enhancement of photoresponse at the conducting interface of LaVO 3 –SrTiO 3 under the simultaneous application of light and negative gate bias voltage, in comparison to their individual application. On the other hand, the illuminated LaVO 3 -SrTiO 3 interface does not show any enhancement, when a positive gate bias voltage is applied. Our x-ray diffractometer, Raman spectroscopy and photoemission measurements show that unlike the LaAlO 3 –SrTiO 3 interface, migration of oxygen vacancies may not be the prime mechanism for the enhanced photoresponse. Rather, we suggest that the photoresponse of our system is intrinsic and this intrinsic mechanism is a complex interplay between band filling, electric field at the interface and modification of conducting channel width.

Locations

• Journal of Physics D Applied Physics - View
• arXiv (Cornell University) - View - PDF