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arXiv · 2107.02870

Expansion of the high field-boosted superconductivity in UTe2 under pressure

Abstract

Magnetic field induced superconductivity is a fascinating quantum phenomenon, whose origin is yet to be fully understood. The recently discovered spin triplet superconductor, UTe2, exhibits two such superconducting phases, with the second one reentering in the magnetic field of 45 T and persisting up to 65 T. More surprisingly, in order to induce this superconducting phase, the magnetic field has to be applied in a special angle range, not along any high symmetry crystalline direction. Here we investigated the evolution of this high-field induced superconducting phase under pressure. Two superconducting phases merges together under pressure, and the zero resistance persists up to 45 T, the field limit of the current study. We also reveal that the high field-induced superconducting phase is completely decoupled from the first order field polarized phase transition, different from previously known example of field induced superconductivity in URhGe, indicating a superconductivity boosted by a different paring mechanism.

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Sheng Ran, Shanta R. Saha, I-Lin Liu, David Graf, Johnpierre Paglione, Nicholas P. Butch. 2021-07-06. Expansion of the high field-boosted superconductivity in UTe2 under pressure. https://doi.org/10.1038/s41535-021-00376-9

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