Zero bias conductance peak in an SNS weak link bicrystal of the triplet superconductor (TMTSF)2ClO4

We report differential conductance measurements across the barrier of a unique bicrystal of the molecular organic superconductor (TMTSF) 2 ClO 4 . A zero temperature superconducting energy gap of 2Δ ∼ 4.2k B T c is estimated from the data, and a large zero-bias conductance peak is detected. We interpret the ZBCP as due to Andreev bound states at the normal-superconducting interface(s) formed at the bicrystal junction, suggesting an SNS structure with spin triplet symmetry. We also report on growth of hybrid (TMTSF) 2 ClO 4 / (TMTSF) 2 PF 6 bicrystals for further studies of superconducting, SDW and FISDW energy gaps.