Superconductivity at 7.3 K in the 133-type Cr-based RbCr 3 As 3 single crystals

Here we report the preparation and superconductivity of the 133-type Cr-based quasi–one-dimensional (Q1D) RbCr 3 As 3 single crystals. The samples were prepared by the deintercalation of Rb + ions from the 233-type Rb 2 Cr 3 As 3 crystals which were grown from a high-temperature solution growth method. The RbCr 3 As 3 compound crystallizes in a centrosymmetric structure with the space group P 6 3 / m (No. 176) different from its non-centrosymmetric Rb 2 Cr 3 As 3 superconducting precursor, and the refined lattice parameters are and . Electrical resistivity and magnetic susceptibility characterizations reveal the occurrence of superconductivity with an interestingly higher onset T c of 7.3 K than other Cr-based superconductors, and an estimated high upper critical field H c 2 (0) about 72.4 T in this 133-type RbCr 3 As 3 crystals.