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arXiv · 2412.08991

Type-I/Type-II superconductivity in noncentrosymmetric compound Ir$_2$Ga$_9$

J. C. Jiao·K. W. Chen·O. O. Bernal·P. -C. Ho·L. Shu
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Abstract

We have performed magnetization, specific heat, and muon spin relaxation ($\mu$SR) measurements on single crystals of the noncentrosymmetric superconductor Ir$_{2}$Ga$_{9}$. The isothermal magnetization measurements show that there is a crossover from Type-I to Type-II superconductivity with decreasing temperature. Potential multi-band superconductivity of Ir$_{2}$Ga$_{9}$~is observed in the specific heat data. $\mu$SR~measurement is performed to map the phase diagram of Ir$_{2}$Ga$_{9}$, and both Type-I and Type-II superconductivity characteristics are obtained. Most importantly, a more unique region with the coexistence of Type-I and Type-II $\mu$SR signals is observed. In addition, time reversal symmetry is found to be preserved in Ir$_{2}$Ga$_{9}$ by zero field $\mu$SR measurement.

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J. C. Jiao, K. W. Chen, O. O. Bernal, P. -C. Ho, L. Shu. 2024-12-12. Type-I/Type-II superconductivity in noncentrosymmetric compound Ir$_2$Ga$_9$. https://arxiv.org/abs/2412.08991

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