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تسجيل مستخدم جديدHeat capacity of type I superconductivity in the Dirac semimetal PdTe$_2$
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Type I superconductivity has recently been reported for the Dirac semimetal PdTe$_2$ (Tc approximately 1.6K) with, remarkably, multiple critical fields and a complex phase diagram. Here, measurements of the specific heat utilizing a thermal relaxation technique are presented. Conventional weak-coupling BCS superconductivity is confirmed by examining the temperature dependence of the specific heat in zero field. By probing the latent heat accompanying the superconducting transition, thermodynamic evidence for type I superconductivity is attained. The presence of the intermediate state is observed as a significant broadening of the superconducting transition onto lower temperatures at high fields as well as irreversibility in the specific heat in zero field cooled data at 8.5 mT.
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The transition metal dichalcogenide PdTe$_2$ was recently shown to be a unique system where a type II Dirac semimetallic phase and a superconducting phase co-exist. This observation has led to wide speculation on the possibility of the emergence of a
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The superconductor PdTe$_2$ was recently classified as a Type II Dirac semimetal, and advocated to be an improved platform for topological superconductivity. Here we report magnetic and transport measurements conducted to determine the nature of the
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The type-II Dirac semimetal PdTe2 was recently reported to be a type-I superconductor with a superconducting transition temperature Tc = 1.65 K. However, the recent results from tunneling and point contact spectroscopy suggested the unusual state of
a mixture of type-I and type-II superconductivity. These contradictory results mean that there is no clear picture of the superconducting phase diagram and warrants a detailed investigation of the superconducting phase. We report here the muon spin rotation and relaxation ($mu$SR) measurements on the superconducting state of the topological Dirac semimetal PdTe2. From $mu$SR measurements, we find that PdTe2 exhibits mixed type-I/type-II superconductivity. Using these results a phase diagram has been determined. In contrast to previous results where local type-II superconductivity persists up to Hc2 = 600 G, we observed that bulk superconductivity is destroyed above 225 G.
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