Tuning the ground state of cuprate high-critical-temperature superconducting thin films by nanofaceted substrates

G. Mirarchi; R. Arpaia; E. Wahlberg; T. Bauch; A. Kalaboukhov; S. Caprara; C. Di Castro; M. Grilli; F. Lombardi; G. Seibold

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arXiv · 2306.12335

Tuning the ground state of cuprate high-critical-temperature superconducting thin films by nanofaceted substrates

G. Mirarchi·R. Arpaia·E. Wahlberg·T. Bauch·A. Kalaboukhov·S. Caprara·C. Di Castro·M. Grilli·F. Lombardi·G. Seibold

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Abstract

Anisotropic transport properties have been assessed in a number of cuprate superconductors, providing evidence for a nematic state. Here, we analyze recent experimental data for ultrathin YBa$_2$Cu$_3$O$_{7-x}$ (YBCO) films, where nematicity is induced via strain engineering, leading to a suppression of charge density wave scattering along the orthorhombic a-axis and a concomitant enhancement of strange metal behavior along the b-axis. It is shown that the anisotropic properties strongly depend on the substrate, which we characterize by atomic force microscopy (AFM). Based on the AFM data, we provide a microscopic model that can account for the absence (presence) of nematicity and the resulting transport properties in films grown on SrTiO$_3$ (MgO) substrates.

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G. Mirarchi, R. Arpaia, E. Wahlberg, T. Bauch, A. Kalaboukhov, S. Caprara, C. Di Castro, M. Grilli, F. Lombardi, G. Seibold. 2023-06-21. Tuning the ground state of cuprate high-critical-temperature superconducting thin films by nanofaceted substrates. https://arxiv.org/abs/2306.12335

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