Angular-dependent muon-spin rotation and torque magnetometry on the mixed state of the high-temperature superconductor YBa2Cu3O7-delta

Muon-spin rotation (mu SR) and torque magnetometry have been used to probe the anisotropy of an untwinned single crystal of YBa2Cu3O7-delta. The absen ce of twin planes allows the ratios of all three principal components of th e superconducting effective mass tensor to be determined. The values for th e in-plane anisotropy are in good agreement with values obtained by other t echniques. The out-of-plane anisotropies as measured by mu SR are also foun d to be in good agreement with other microscopic measurements, but somewhat lower than those resulting from torque measurements on this and other crys tals.