Study of the new superconducting compound Zr0.97V0.03B2 with point-contact spectroscopy

TL;DR

This study investigates the superconducting energy gap of Zr0.97V0.03B2 using point-contact spectroscopy, revealing a strong coupling superconductivity with a transition at 9.3 K and an energy gap ratio indicating very strong coupling.

Contribution

The paper provides the first detailed measurement of the superconducting energy gap and its temperature evolution in Zr0.97V0.03B2 using point-contact spectroscopy.

Findings

Superconducting transition temperature at 9.3 K.

Energy gap ratio 2Δ(0)/k_B T_c ≈ 8.95 indicating strong coupling.

Gap evolution consistent with BCS theory.

Abstract

We present a study of the superconducting energy gap performed with point contact spectroscopy in a single crystal of the superconductor Zr0:97V0:03B2. We determined the size and evolution with temperature of the energy gap, the transition temperature in the compound occurs at the onset of Tc = 9.3 K. The point contact junctions were measured from 1.7 to 20 K. The differential conductance as a function of bias voltage was analyzed with the Blonder-Tinkham-Klapwijk model, the evolution of the gap with temperature was compared with the BCS theory, the ratio 2{\Delta}(0)/KBTC was of the order of 8.95 indicative of a very strong coupling limit.