Measurement Of The London Penetration Depths In Yba2cu3ox By Means Of Muon Spin Rotation (Mu-Sr) Experiments

To get accurate values of the London penetration depths in YBa 2 Cu 3 O x , μSR measurements were performed on a high quality, sintered sample and a c-axis-oriented polycrystal. For the sintered sample the temperature dependence of the effective penetration depth λ eff is well described by the two-fluid model, with λ eff (0) = 155(10) nm. This behavior of λ eff ( T ) is consistent with conventional s-wave pairing. The anisotropy ratio λ c λ ab ⋍ 5(1) was determined from measurements on the polycrystal. These results were used to calculate λ ab (0) = 130(10) nm and λ c (0) ⋍ 500 – 800 nm .