Full superconducting gap in the candidate topological superconductor In$_{1-x}$Pb$_x$Te for x = 0.2

M. P. Smylie; Kaya Kobayashi; J. Z. Dans; H. Hebbeker; R. Chapai; W. -K. Kwok; U. Welp

doi:10.1103/physrevb.106.054503

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arXiv · 2204.07635

Full superconducting gap in the candidate topological superconductor In$_{1-x}$Pb$_x$Te for x = 0.2

M. P. Smylie·Kaya Kobayashi·J. Z. Dans·H. Hebbeker·R. Chapai·W. -K. Kwok·U. Welp

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Abstract

High-pressure synthesis techniques have allowed for the growth of samples on the indium-rich side of (Pb,In)Te, which have increased superconducting transition temperatures compared to lead-rich compounds. In this study we present measurements of the temperature dependence of the London penetration depth $\Delta \lambda(T)$ in the compound In$_{0.8}$Pb$_{0.2}$Te, which shows a bulk $T_{c,onset}$ of $\sim4.75$ K. The results indicate fully gapped BCS-like behavior, ruling out odd-parity, topologically nontrivial $A_{2u}$ pairing; however, odd-parity $A_{1u}$ pairing is still possible. Critical field values measured below 1 K and other superconducting parameters are also presented.

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M. P. Smylie, Kaya Kobayashi, J. Z. Dans, H. Hebbeker, R. Chapai, W. -K. Kwok, U. Welp. 2022-04-15. Full superconducting gap in the candidate topological superconductor In$_{1-x}$Pb$_x$Te for x = 0.2. https://doi.org/10.1103/physrevb.106.054503

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