Transition of stoichiometricSr2VO3FeAs to a superconducting state at 37.2 K

TL;DR

This paper reports the fabrication of a new layered superconductor Sr4V2O6Fe2As2 with a transition temperature of 37.2 K, demonstrating bulk superconductivity, high anisotropy, and electron-like charge carriers, with potential induction mechanisms involving oxygen deficiency or vanadium valence states.

Contribution

It introduces a new layered superconductor with detailed structural, magnetic, and electronic properties, highlighting its high critical field and anisotropic behavior.

Findings

Superconducting transition at 37.2 K confirmed by diamagnetization and zero resistance.

High upper critical field and large vortex liquid region observed.

Electron-like charge carriers identified via Hall effect measurements.

Abstract

The superconductor Sr4V2O6Fe2As2 with transition temperature at 37.2 K has been fabricated. It has a layered structure with the space group of p4/nmm, and with the lattice constants a = 3.9296Aand c = 15.6732A. The observed large diamagnetization signal and zero-resistance demonstrated the bulk superconductivity. The broadening of resistive transition was measured under different magnetic fields leading to the discovery of a rather high upper critical field. The results also suggest a large vortex liquid region which reflects high anisotropy of the system. The Hall effect measurements revealed dominantly electron-like charge carriers in this material. The superconductivity in the present system may be induced by oxygen deficiency or the multiple valence states of vanadium.