Charging effects and anomalous resistive features of superconducting boron doped diamond films

TL;DR

This study investigates anomalous resistive peaks and charge-related transitions in heavily boron-doped diamond films, revealing a Charge-BKT transition and potential for switching device applications.

Contribution

It demonstrates the presence of a Charge-BKT transition in boron-doped diamond films, linking resistive anomalies to charge defect pinning and collective charge phenomena.

Findings

Resistive peaks follow a BKT-like temperature dependence.

Non-linear magnetoresistance shows temperature-dependent peaks.

Hysteresis in I-V curves indicates charge defect pinning.

Abstract

Anomalous resistive peaks below the superconducting transition temperature in heavily boron doped nanocrystalline diamond films could have potential application in switching devices, however the exact origin is still under study. We establish a temperature dependence of this resistive phase similar to what has been reported for in Josephson junction arrays and other granular superconductors where the charge duel of the Berezinskii-Kosterlitz-Thouless (BKT) transition has been observed. Non-linear magnetoresistance with a temperature dependent peak feature below the critical field are also presented. Pronounced temperature dependent hysteresis in the current voltage sweeps at temperatures below the determined BKT critical point are related to pinning of charge defects. It is shown that these collective features allude to a Charge-BKT transition between charge and anti-charge analogues.