Robust superconductivity and transport properties in (Li1-xFex)OHFeSe single crystals

TL;DR

This study reports the successful growth and characterization of (Li${_{1-x}}$Fe${_x}$)OHFeSe single crystals, demonstrating robust superconductivity with a transition temperature around 38.3K and high critical current densities, highlighting its potential for superconducting applications.

Contribution

First successful growth of (Li${_{1-x}}$Fe${_x}$)OHFeSe single crystals and detailed analysis of their superconducting and transport properties.

Findings

Superconducting transition temperature around 38.3K.

Large critical current density observed at low temperatures.

Superconductivity remains robust under various magnetic fields.

Abstract

The recently discovered (Li${_{1-x}}$Fe${_x}$)OHFeSe superconductor with $T_c$ about 40K provides a good platform for investigating the magnetization and electrical transport properties of FeSe-based superconductors. By using a hydrothermal ion-exchange method, we have successfully grown crystals of (Li${_{1-x}}$Fe${_x}$)OHFeSe. X-ray diffraction on the sample shows the single crystalline PbO-type structure with the c-axis preferential orientation. Magnetic susceptibility and resistive measurements show an onset superconducting transition at around ${T_c}$=38.3K. Using the magnetization hysteresis loops and Bean critical state model, a large critical current ${J_s}$ is observed in low temperature region. The critical current density is suppressed exponentially with increasing magnetic field. Temperature dependencies of resistivity under various currents and fields are measured, revealing a robust superconducting current density and bulk superconductivity.