Study of the anisotropic g-factors for Dy 3+ ions in DyBa 2Cu 3O 6+ x superconductor

Abstract

The perturbation formulae of EPR g-factors g x , g y and g z for the lowest Kramers doublet of 4f 9 ion in rhombic symmetry are established. In these formulae, the contributions to g-factors are considered due to J-mixing among the ground 6H 15/2, the first excited 6H 13/2 and second excited 6H 11/2 states via crystal-field interaction, the admixtures among the states with the same J value via spin–orbit coupling interaction and those between the lowest Kramers doublet Γr and other 20 Kramers doublets Γ X within the states 6H J ( J=15/2, 13/2 and 11/2) via crystal-field and orbital angular momentum interactions. According to these formulae, the g-factors g x , g y and g z for Dy 3+ ions in DyBa 2Cu 3O 6+ x superconductor are calculated. The results are in reasonable agreement with the observed values.