μ+SR study of two-dimensional antiferromagnets, delafossite-type compounds

Abstractμ+SR experiments were performed on delafossite-type compounds, CuCrO2, AgCrO2, CuFeO2, which are model compounds of triangular lattice antiferromagnets. The initial asymmetries are much smaller than the expected value, implying muonium formation. The time spectra are composed of slow andfast relaxation components. We attributed the components to signals from μ+ stopped at the center of O2− ions andmuonium far from nuclear dipole moments, respectively. The asymmetries decrease belowTN but no precession spectra were observed. Relaxation rates of slow andfast relaxation components show maxima atTN.