Paramagnetic Meissner effect and magnetic remanence in granular MgB2

Abstract

The magnetic response of MgB2 samples prepared by solid state reaction method, were studied. Important features revealing the granular character of the specimens were verified, as (i) depressed magnetization versus field response, when compared with the corresponding curve for unlinked powder, (ii) the paramagnetic Meissner effect and (iii) the occurrence of a magnetic remanence in a limited interval of temperatures. Experimental evidence is added to indicate that these effects are related to flux pinning.