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تسجيل مستخدم جديدSuperconductivity, pairing symmetry, and disorder in the doped topological insulator Sn$_{1-x}$In$_x$Te for x $geq$ 0.10
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The temperature dependence of the London penetration depth $Deltalambda(T)$ in the superconducting doped topological crystalline insulator Sn$_{1-x}$In$_x$Te was measured down to 450 mK for two different doping levels, x $approx$ 0.45 (optimally doped) and x $approx$ 0.10 (underdoped), bookending the range of cubic phase in the compound. The results indicate no deviation from fully gapped BCS-like behavior, eliminating several candidate unconventional gap structures. Critical field values below 1 K and other superconducting parameters are also presented. The introduction of disorder by repeated particle irradiation with 5 MeV protons does not enhance $T_c$, indicating that ferroelectric interactions do not compete with superconductivity.
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