Observation of various magnetic-field-induced states in B20 cubic MnGe

Abstract

We report on the magnetic properties of the B20 polycrystalline MnGe compound synthesized under high-temperature and high-pressure conditions. From isothermal ac susceptibility experiments, we found the presence of several different magnetic-field-induced phases presenting similarities with those in the isostructural compounds MnSi and FeGe but with much broader existence range in the (B, T) domain. From anomalies found in the ac magnetic susceptibility, we found not only the presence of an A phase similar to the one observed in MnSi but also a second phase we call B, whose magnetic signature is very similar to that of the A phase. Our discovery indicates that MnGe is a promising compound in order to further explore the existence conditions of the phases containing skyrmions.