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.

11 pages, 5 figures

References in corpus (1)

• Superconductivity in single-layer films of FeSe with a transition temperature above 100 K

Cited by in corpus (1)

• On the Remarkable Superconductivity of FeSe and its Close Cousins