A novel approach to determine blocking temperature in bulk materials

Abstract

Abstract Blocking temperature (θB) holds utmost significance in magnetic devices. A novel approach to ascertain the θB for bulk materials has been propounded. The θB has been correlated with the magnetic entropy change (ΔS) during zero-field cooled (ZFC) and field cooled (FC) magnetization. The values of ΔS have been calculated in µB/f.u.K. The θB has been investigated for two distinct cases – (I) with ZFC magnetization reversal and (II) without ZFC magnetisation reversal. Based on the reported experimental approach, a novel definition of θB has been propounded for bulk materials. The combined analysis of ZFC and FC magnetization behaviour provides a better approximation of θB for bulk materials.