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arXiv · 1708.00198

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

Andrea Rubano·Tim Günter·Manfred Fiebig·Fabio Miletto Granozio·Lorenzo Marrucci·Domenico Paparo
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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.

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Andrea Rubano, Tim Günter, Manfred Fiebig, Fabio Miletto Granozio, Lorenzo Marrucci, Domenico Paparo. 2017-08-01. Ultrafast Modification of the Polarity at LaAlO$_3$/SrTiO$_3$ Interfaces. https://doi.org/10.1103/physrevb.97.035438

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