Enhancement of superconducting transition temperature in electrochemically etched FeSe/LaAlO${}_3$ films

Abstract

In this study, we investigated the gate voltage dependence of $T_{\mathrm{c}}$ in electrochemically etched FeSe films with an electric-double layer transistor structure. The $T_{\mathrm{c}}^{\mathrm{zero}}$ value of the etched FeSe films with a lower gate voltage ($V_{\mathrm{g}}$ = 2.5 and 3.3 V) reaches 46 K, which is the highest value among almost all reported values from the resistivity measurements except for the data by Ge et al. This enhanced $T_{\mathrm{c}}$ remains unchanged even after the discharge process, unlike the results for electrostatic doping without an etching process. Our results suggest that the origin of the increase in $T_{\mathrm{c}}$ is not electrostatic doping but rather the electrochemical reaction at the surface of an etched films.

arXiv comment11 pages, 5 figures

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Cited by in corpus (10)

• On the Remarkable Superconductivity of FeSe and its Close Cousins
• Interface superconductivity in FeSe thin films on SrTiO${}_3$grown by the PLD technique
• Positive and negative chemical pressure effects investigated in electron-doped FeSe films with an electric-double-layer structure
• Relationships between Superconductivity and Nematicity in FeSe${}_{1-x}$Te${}_x$ ($x=0-0.5$) Films Studied by Complex Conductivity Measurements
• Anisotropy of upper critical fields and interface superconductivity in FeSe/SrTiO3 grown by PLD
• Transport properties around the metal-insulator transition for SrVO3 ultrathin films fabricated by electrochemical etching
• Sulfur-induced magnetism in FeSe${}_{1-x}$S${}_x$ thin films on LaAlO${}_3$ revealed by muon spin rotation/relaxation
• Studies of superconductivity of Fe chalcogenides in films grown by PLD technique
• What controls the superconducting dome of electron-doped FeSe?
• Fabrication of oxide/FeSe multilayer films using the PLD technique