Magnetism and electrical resistivity of ErCo2 under high pressure

By measuring the temperature dependencies of the electrical resistivity rho (T) of ErCo2 under hydrostatic pressure P up to 8 GPa, extended information on pressure effects on magnet ism in this material has been obtained. This is enabled by the fact that the magnetic phenomena around T-C are reflected in strong anomalies of electrical resistivity, Values of both, the Curie temperature T-C, and resistivity rho well above T-C are substantially influenced by applied pressure. Initially, Tc decreases linearly with increasing P up to approximate to 1.5 GPa. Beyond 1.5 Gpa, however, the T-C vs. p data gradually deviate from the extrapolated linear dependence to become almost pressure independent (approximate to 13 K) around 8 GPa. Also the shape of the rho (T) anomaly at T-C is considerably modified. The loss of Co magnetism is indicated by vanishing resistivity drop at T-C for P > 4 GPa where T(C)approximate to const. I his behavior is discussed within a model assuming that for P > P-C the projected Co-3d density of states in the vicinity of E-F decreases, the itinerant Co moment vanishes because the RE-Co-RE exchange channel becomes ineffective to induce splitting of the Co 3d majority and minority subbands.