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 LaAlO3/SrTiO3 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 LaAlO3/SrTiO3 interface state. Here we show that the polarization state at the LaAlO3/SrTiO3 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.
@article{arxiv.1708.00198,
title = {Ultrafast Modification of the Polarity at LaAlO$_3$/SrTiO$_3$ Interfaces},
author = {Andrea Rubano and Tim Günter and Manfred Fiebig and Fabio Miletto Granozio and Lorenzo Marrucci and Domenico Paparo},
journal= {arXiv preprint arXiv:1708.00198},
year = {2018}
}