Visible light enhanced field effect at LaAlO3/SrTiO3 interface

Abstract

Electrical field and light-illumination have been two most widely used stimuli in tuning the conductivity of semiconductor devices. Via capacitive effect electrical field modifies the carrier density of the devices, while light-illumination generates extra carriers by exciting trapped electrons into conduction band1. Here, we report on an unexpected light illumination enhanced field effect in a quasi-two-dimensional electron gas (q2DEG) confined at the LaAlO3/SrTiO3 (LAO/STO) interface which has been the focus of emergent phenomenon exploration2-14. We found that light illumination greatly accelerates and amplifies the field effect, driving the field-induced resistance growth which originally lasts for thousands of seconds into an abrupt resistance jump more than two orders of magnitude. Also, the field-induced change in carrier density is much larger than that expected from the capacitive effect, and can even be opposite to the conventional photoelectric effect. This work expands the space for novel effect exploration and multifunctional device design at complex oxide interfaces.

References in corpus (4)

• Magnetic effects at the interface between nonmagnetic oxides
• Electric Field Control of the LaAlO${}_3$/SrTiO${}_3$ Interface Ground State
• Strain gradient induced polarization in SrTiO3 single crystals
• Static and Ultrafast Dynamics of Defects of SrTiO3 in LaAlO3/SrTiO3 Heterostructures

Cited by in corpus (5)

• Observation of Inverse Edelstein Effect in Rashba-Split 2DEG between SrTiO3 and LaAlO3 at Room Temperature
• Giant tunability of the two-dimensional electron gas at the interface of gamma-Al2O3/SrTiO3
• Tuning the two-dimensional electron liquid at oxide interfaces by buffer-layer-engineered redox reactions
• Suppressed carrier density for the patterned high mobility two-dimensional electron gas at gamma-Al2O3/SrTiO3 heterointerfaces
• Dynamic Modulation of the Transport Properties of the LaAlO3/SrTiO3 Interface Using Uniaxial Strain