μ+ Knight shift and spin relaxation in indium single crystal

μ+SR measurements have been performed in a single crystal indium sample between 12 K and 300 K with a stroboscopic μSR spectrometer. The muonic Knight shift Kμ and the muonic depolarization rate σ were obtained for various angles θ between the tetragonal crystalline c-axis and the direction of the external field. The isotropic part of Kμ is only weakly temperature dependent and is consistent with the estimated Pauli spin susceptibility value. At a temperature of 12 K the angular dependence of M2 (the second moment of the field distribution at the muon, obtained from the measured σ(θ) values) allows a clear determination of the muon location - the symmetric tetrahedral site. The observed anisotropic Kμ cannot be explained by the dipoles at the In atoms responsible for the bulk magnetic susceptibility but probably originates from an anisotropic Pauli spin susceptibility. (orig.)