Electron spin resonance of Er3+ in YBiPt

Electron spin resonance (ESR) experiments at 4.15 K of Er3+ in YBiPt show that Er3+ is in a site of cubic local symmetry, with a Γ(3)8 ground state and an overall crystal field splitting of ∼ 85(10) K. We inferred from the spectra the existence of lattice distortions at the rare-earth (RE) site. These results may help in understanding the heavy-fermion system YbBiPt, which has the same structure as YBiPt