Superconductivity in heavily boron-doped silicon carbide

TL;DR

This paper reports the discovery of superconductivity in heavily boron-doped silicon carbide, a semiconducting material, and investigates which crystal phase contributes to this phenomenon.

Contribution

It provides evidence that hexagonal silicon carbide can exhibit superconductivity when heavily doped with boron, expanding the understanding of superconductivity in semiconductors.

Findings

Superconductivity observed in heavily boron-doped SiC.

Hexagonal SiC phase participates in superconductivity.

No cubic SiC phase detected in the studied sample.

Abstract

The discoveries of superconductivity in heavily boron-doped diamond (C:B) in 2004 and silicon (Si:B) in 2006 renew the interest in the superconducting state of semiconductors. Charge-carrier doping of wide-gap semiconductors leads to a metallic phase from which upon further doping superconductivity can emerge. Recently, we discovered superconductivity in a closely related system: heavily-boron doped silicon carbide (SiC:B). The sample used for that study consists of cubic and hexagonal SiC phase fractions and hence this lead to the question which of them participates in the superconductivity. Here we focus on a sample which mainly consists of hexagonal SiC without any indication for the cubic modification by means of x-ray diffraction, resistivity, and ac susceptibility.