Title: Multiband Superconductivity in the time reversal symmetry broken superconductor Re6Zr,
Abstract: We report point contact Andreev Reflection (PCAR) measurements on a
high-quality single crystal of the non-centrosymmetric superconductor Re6Zr. We
observe that the PCAR spectra can be fitted by taking two isotropic
superconducting gaps with Delta_1 ~ 0.79 meV and Delta_2 ~ 0.22 meV
respectively, suggesting that there are at least two bands which contribute to
superconductivity. Combined with the observation of time reversal symmetry
breaking at the superconducting transition from muon spin relaxation
measurements (Phys. Rev. Lett. 112, 107002 (2014)), our results imply an
unconventional superconducting order in this compound: A multiband singlet
state that breaks time reversal symmetry or a triplet state dominated by
interband pairing.