Evidence of multiband behavior in a new superconductor Ta0.8Zr0.2B with FeB-prototype structure

We present results that show a relation between crystalline structure and superconductivity in the Ta1-xZrxB system. The substitution of Ta for Zr atoms induces a crystal structure change from CrB- to FeB-prototype structure in which superconductivity is present with higher superconducting critical temperature Tc. The interrelation between Tc and Zr content shows a dome-like behavior with maximum Tc at x = 0.2. In this sample, bulk superconductivity was observed and characterized by magnetization, electrical resistivity and specific heat measurements, all consistent with a superconducting critical temperature close to 7.8 K. The upper and lower critical field diagrams have no usual behavior which may be connected to a multiband scenario.

Source: Journal of Alloys and Compounds - June 17, 2019 Category: Chemistry Source Type: research