title: Visible-light-enhanced gating effect at the LaAlO₃/SrTiO₃ interface.
abstract: Electrostatic gating field and light illumination are two widely used stimuli for semiconductor devices. Via capacitive effect, a gate field modifies the carrier density of the devices, while illumination generates extra carriers by exciting trapped electrons. Here we report an unusual illumination-enhanced gating effect in a two-dimensional electron gas at the LaAlO3/SrTiO3 interface, which has been the focus of emergent phenomena exploration. We find that light illumination decreases, rather than increases, the carrier density of the gas when the interface is negatively gated through the SrTiO3 layer, and the density drop can be 20 times as large as that caused by the conventional capacitive effect. This effect is further found to stem from an illumination-accelerated interface polarization, an originally extremely slow process. This unusual effect provides a promising controlling of the correlated oxide electronics in which a much larger gating capacity is demanding due to their intrinsic larger carrier density.
authors.affiliation: Beijing National Laboratory for Condensed Matter &Institute of Physics, Chinese Academy of Sciences, Beijing 100190, China.
authors.forename: Y
authors.initials: Y
authors.lastname: Lei
authors.affiliation: Beijing National Laboratory for Condensed Matter &Institute of Physics, Chinese Academy of Sciences, Beijing 100190, China.
authors.forename: Y
authors.initials: Y
authors.lastname: Li
authors.affiliation: Department of Energy Conversion and Storage, Technical University of Denmark, Risø Campus, 4000 Roskilde, Denmark.
authors.forename: Y Z
authors.initials: YZ
authors.lastname: Chen
authors.affiliation: Geballe Laboratory for Advanced Materials and Stanford Institute for Materials &Energy Sciences, Stanford University, Stanford, California 94305, USA.
authors.forename: Y W
authors.initials: YW
authors.lastname: Xie
authors.affiliation: Beijing National Laboratory for Condensed Matter &Institute of Physics, Chinese Academy of Sciences, Beijing 100190, China.
authors.forename: Y S
authors.initials: YS
authors.lastname: Chen
authors.affiliation: Beijing National Laboratory for Condensed Matter &Institute of Physics, Chinese Academy of Sciences, Beijing 100190, China.
authors.forename: S H
authors.initials: SH
authors.lastname: Wang
authors.affiliation: Beijing National Laboratory for Condensed Matter &Institute of Physics, Chinese Academy of Sciences, Beijing 100190, China.
authors.forename: J
authors.initials: J
authors.lastname: Wang
authors.affiliation: Beijing National Laboratory for Condensed Matter &Institute of Physics, Chinese Academy of Sciences, Beijing 100190, China.
authors.forename: B G
authors.initials: BG
authors.lastname: Shen
authors.affiliation: Department of Energy Conversion and Storage, Technical University of Denmark, Risø Campus, 4000 Roskilde, Denmark.
authors.forename: N
authors.initials: N
authors.lastname: Pryds
authors.affiliation: Geballe Laboratory for Advanced Materials and Stanford Institute for Materials &Energy Sciences, Stanford University, Stanford, California 94305, USA.
authors.forename: H Y
authors.initials: HY
authors.lastname: Hwang
authors.affiliation: Beijing National Laboratory for Condensed Matter &Institute of Physics, Chinese Academy of Sciences, Beijing 100190, China.
authors.forename: J R
authors.initials: JR
authors.lastname: Sun