Nodeless superconducting gap in the candidate topological superconductor Sn1-xInxTe for x=0.7

High-pressure synthesis techniques have allowed for the growth of Sn1-xInxTe samples beyond the ambient In-saturation limit of x = 0.5 (T-c similar to 4.5 K). In this study we present measurements of the temperature dependence of the London penetration depth Delta lambda(T) in this superconducting doped topological insulator for x = 0.7, where T-c(,onset) approximate to 5 K. The results indicate fully gapped BCS-like behavior, ruling out odd-parity A(2u), pairing; however, odd-parity A(1u) in pairing is still possible. Critical field values measured below 1 K and other superconducting parameters are also presented.