Observation of structural anomaly and low-field magnetocaloric effect in Cu2OSeO3

Abstract We report here the detailed investigation on structural and magnetic behavior of the polycrystalline sample of Cu2OSeO3. The Mott insulator Cu2OSeO3 is a fascinating material showing skyrmionic state and magneto-electric coupling. We observe clear signature of thermal hysteresis between field-cooled and field-cooled heating data in the low-field magnetization versus temperature curve just below the magnetic ordering temperature of TC ~ 60 K. Temperature dependent powder x-ray diffraction data indicate the presence of lattice anomaly below TC. The sample also shows reasonable value of conventional magnetocaloric effect for small value of applied magnetic field, which can be related to the change in the magnetic structure with field.