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arXiv · 1810.11265

Observation of Half-Quantum Flux in Unconventional Superconductor $\beta$-Bi$_2$Pd

Yufan Li·Xiaoying Xu·C. L. Chien
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Abstract

We report the observation of half-integer magnetic flux quantization in mesoscopic rings of superconducting $\beta$-Bi$_2$Pd thin films. The half-quantum fluxoid manifests itself as a $\pi$ phase shift in the quantum oscillation of the critical temperature. This result verifies unconventional superconductivity of $\beta$-Bi$_2$Pd, in accord with the expectation of a topological superconductor. We also discuss the strong indication that $\beta$-Bi$_2$Pd is a spin-triplet superconductor.

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Yufan Li, Xiaoying Xu, C. L. Chien. 2018-10-26. Observation of Half-Quantum Flux in Unconventional Superconductor $\beta$-Bi$_2$Pd. https://doi.org/10.1126/science.aau6539

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