Superconductivity and Magnetism in Noncentrosymmetric RhGe

TL;DR

This study reports the discovery of superconductivity coexisting with weak ferromagnetism in RhGe under high pressure, revealing a noncentrosymmetric ferromagnetic superconductor with a pressure-dependent phase diagram.

Contribution

It provides the first experimental evidence of superconductivity in noncentrosymmetric RhGe and explores its magnetic and electronic properties through measurements and simulations.

Findings

Superconductivity observed below 4.5 K in RhGe.

Weak ferromagnetism present below 140 K.

Superconducting dome with maximum T_c near 4 GPa.

Abstract

RhGe synthesized at high pressure is crystallized in noncentrosymmetric cubic structure of the B20 type. Measurements of the electrical resistivity and magnetization demonstrate a superconducting state below T$_c$ ~ 4.5 K and a weak ferromagnetism below T$_m$ ~ 140 K. Specific heat data confirm the bulk nature of superconductivity in this ferromagnetic superconductor. The superconducting region forms a dome on the P-T diagram with a maximum of T$_c$ near 4 GPa. Ab initio simulations suggest that the observed weak magnetization emerges from the pronounced spin polarization with magnetic quadrupole and toroidal moments located at Rh and Ge sites.