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arXiv · 2102.07153

Gate-tunable electron interaction in high-{\kappa} dielectric films

Svitlana Kondovych·Igor Luk'yanchuk·Tatyana I. Baturina·Valerii M. Vinokur
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Abstract

The two-dimensional (2D) logarithmic character of Coulomb interaction between charges and the resulting logarithmic confinement is a remarkable inherent property of high dielectric constant (high-$\kappa$) thin films with far reaching implications. Most and foremost, this is the charge Berezinskii-Kosterlitz-Thouless transition with the notable manifestation, low-temperature superinsulating topological phase. Here we show that the range of the confinement can be tuned by the external gate electrode and unravel a variety of electrostatic interactions in high-$\kappa$ films. We find that by reducing the distance from the gate to the film, we decrease the spatial range of the 2D long-range logarithmic interaction, changing it to predominantly dipolar or even to exponential one at lateral distances exceeding the dimension of the film-gate separation. Our findings offer a unique laboratory for the in-depth study of topological phase transitions and related phenomena that range from criticality of quantum metal- and superconductor-insulator transitions to the effects of charge-trapping and Coulomb scalability in memory nanodevices.

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Svitlana Kondovych, Igor Luk'yanchuk, Tatyana I. Baturina, Valerii M. Vinokur. 2021-02-14. Gate-tunable electron interaction in high-{\kappa} dielectric films. https://doi.org/10.1038/srep42770

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