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arXiv · 2206.13555

Coupling between tilts and charge carriers at polar-nonpolar perovskite interfaces

Daniel Bennett·Pablo Aguado-Puente·Emilio Artacho·Nicholas Bristowe
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Abstract

The phenomenological theory for the polar instability giving rise to a two-dimensional electron gas at perovskite interfaces is hereby extended to include the coupling to perovskite tilts. A Landau theory for homogeneous tilts is first explored, setting the scene for the further, more realistic Landau-Ginzburg theory describing varying tilt amplitudes across a thin film. The theory is also generalized to account for the response to an applied electric field normal to the interface, which allows a finer control on phase transitions. The conventionally described physics of a single metal-insulator transition is substantially enriched by the coupling, the model describing various scenarios with one or two transitions, possibly continuous or discontinuous. First-principles calculations permit the estimation of the parameters defining the model, which have been calculated for the interface between lanthanum aluminate and strontium titanate.

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Daniel Bennett, Pablo Aguado-Puente, Emilio Artacho, Nicholas Bristowe. 2022-09-19. Coupling between tilts and charge carriers at polar-nonpolar perovskite interfaces. https://doi.org/10.1103/physrevb.106.094106

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