Ultrafast Modification of the Polarity at LaAlO${}_3$/SrTiO${}_3$ Interfaces

Abstract

Oxide growth with semiconductor-like accuracy has led to atomically precise thin films and interfaces that exhibit a plethora of phases and functionalities not found in the oxide bulk material. This yielded spectacular discoveries such as the conducting, magnetic or even superconducting LaAlO${}_3$/SrTiO${}_3$ interfaces separating two prototypical insulating perovskite materials. All these investigations, however, consider the static state at the interface, although studies on fast oxide interface dynamics would introduce a powerful degree of freedom to understanding the nature of the LaAlO${}_3$/SrTiO${}_3$ interface state. Here we show that the polarization state at the LaAlO${}_3$/SrTiO${}_3$ interface can be optically enhanced or attenuated within picoseconds. Our observations are explained by a model based on charge propagation effects in the interfacial vicinity and transient polarization buildup at the interface.

References in corpus (2)

• Origin of charge density at LaAlO3-on-SrTiO3 hetero-interfaces; possibility of intrinsic doping
• Polar catastrophe and electronic reconstructions at the LaAlO3/SrTiO3 interface: evidence from optical second harmonic generation

Cited by in corpus (1)

• Indirect but Efficient: Laser-Excited Electrons Can Drive Ultrafast Polarization Switching in Ferroelectric Materials