Superconductivity Discovered in Niobium Polyhydride at High Pressures

TL;DR

This study reports the synthesis of niobium polyhydride under high pressure, demonstrating superconductivity at 42 K, with detailed characterization of its critical magnetic field and structural phase, advancing high-pressure superconductor research.

Contribution

First synthesis of niobium polyhydride at high pressure showing superconductivity, with detailed magnetic and structural characterization.

Findings

Superconductivity at 42 K observed at 187 GPa

Upper critical magnetic field estimated at ~16.8 Tesla

Structural analysis suggests Fm-3m phase of NbH3 as the superconducting phase

Abstract

Niobium polyhydride was synthesized at high pressure and high temperature conditions by using diamond anvil cell combined with in situ high pressure laser heating techniques. High pressure electric transport experiments demonstrate that superconducting transition occurs with critical temperature(Tc) 42 K at 187 GPa. The shift of Tc as function of external applied magnetic field is in consistent to the nature of superconductivity while the upper critical field at zero temperature Hc2(0) is estimated to~16.8 Tesla while the GL coherent length ~57 angstrom is estimated. The structure investigation using synchrotron radiation implies that the observed superconductivity may come from Fm-3m phase of NbH3.