Non-universal current flow near the metal-insulator transition in an oxide interface

Eylon Persky; Naor Vardi; Ana Mafalda R. V. L. Monteiro; Thierry C. van Thiel; Hyeok Yoon; Yanwu Xie; Benoît Fauqué; Andrea D. Caviglia; Harold Y. Hwang; Kamran Behnia; Jonathan Ruhman; Beena Kalisky

doi:10.1038/s41467-021-23393-5

arXiv · 2103.08658

Non-universal current flow near the metal-insulator transition in an oxide interface

Eylon Persky·Naor Vardi·Ana Mafalda R. V. L. Monteiro·Thierry C. van Thiel·Hyeok Yoon·Yanwu Xie·Benoît Fauqué·Andrea D. Caviglia·Harold Y. Hwang·Kamran Behnia·Jonathan Ruhman·Beena Kalisky

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Abstract

In systems near phase transitions, macroscopic properties often follow algebraic scaling laws, determined by the dimensionality and the underlying symmetries of the system. The emergence of such universal scaling implies that microscopic details are irrelevant. Here, we locally investigate the scaling properties of the metal-insulator transition at the LaAlO3/SrTiO3 interface. We show that, by changing the dimensionality and the symmetries of the electronic system, coupling between structural and electronic properties prevents the universal behavior near the transition. By imaging the current flow in the system, we reveal that structural domain boundaries modify the filamentary flow close to the transition point, preventing a fractal with the expected universal dimension from forming. Our results offer a generic platform to engineer electronic transitions on the nanoscale.

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Eylon Persky, Naor Vardi, Ana Mafalda R. V. L. Monteiro, Thierry C. van Thiel, Hyeok Yoon, Yanwu Xie, Benoît Fauqué, Andrea D. Caviglia, Harold Y. Hwang, Kamran Behnia, Jonathan Ruhman, Beena Kalisky. 2021-03-15. Non-universal current flow near the metal-insulator transition in an oxide interface. https://doi.org/10.1038/s41467-021-23393-5

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