Magnetically Tuned Metal-Insulator Transition in LaAlO$_3$/SrTiO$_3$ Nanowire Arrays

Ranjani Ramachandran; Shashank Anand; Kitae Eom; Kyoungjun Lee; Dengyu Yang; Muqing Yu; Sayanwita Biswas; Aditi Nethwewala; Chang-Beom Eom; Erica Carlson; Patrick Irvin; Jeremy Levy

arXiv · 2410.01937

Magnetically Tuned Metal-Insulator Transition in LaAlO$_3$/SrTiO$_3$ Nanowire Arrays

Ranjani Ramachandran·Shashank Anand·Kitae Eom·Kyoungjun Lee·Dengyu Yang·Muqing Yu·Sayanwita Biswas·Aditi Nethwewala·Chang-Beom Eom·Erica Carlson·Patrick Irvin·Jeremy Levy

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Abstract

A wide family of two dimensional (2D) systems, including stripe-phase superconductors, sliding Luttinger liquids, and anisotropic 2D materials, can be modeled by an array of coupled one-dimensional (1D) electron channels or nanowire arrays. Here we report experiments in arrays of conducting nanowires with gate and field tunable interwire coupling, that are programmed at the LaAlO$_3$/SrTiO$_3$ interface. We find a magnetically-tuned metal-to-insulator transition in which the transverse resistance of the nanowire array increases by up to four orders of magnitude. To explain this behavior, we develop a minimal model of a coupled two-wire system which agrees well with observed phenomena. These nanowire arrays can serve as a model systems to understand the origin of exotic behavior in correlated materials via analog quantum simulation.

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Ranjani Ramachandran, Shashank Anand, Kitae Eom, Kyoungjun Lee, Dengyu Yang, Muqing Yu, Sayanwita Biswas, Aditi Nethwewala, Chang-Beom Eom, Erica Carlson, Patrick Irvin, Jeremy Levy. 2024-10-02. Magnetically Tuned Metal-Insulator Transition in LaAlO$_3$/SrTiO$_3$ Nanowire Arrays. https://arxiv.org/abs/2410.01937

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