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Pauli-limit upper critical field of high-temperature superconductor La_1.84Sr_0.16CuO₄.

ABSTRACT: The upper critical field of a cuprate high-temperature superconductor, La_1.84Sr_0.16CuO₄, was investigated by high-frequency self-resonant contactless electrical conductivity measurements in magnetic fields up to 102?T. An irreversible transition was observed at 85?T (T?=?4.2?K), defined as the upper critical field. The temperature-dependent upper critical field was argued on the basis of the Werthamer-Helfand-Hohenberg theory. The Pauli-limiting pair-breaking process with a small contribution of the spin-orbit coupling explained the first-order phase transition exhibiting a hysteresis observed at low temperatures.

SUBMITTER: Nakamura D

PROVIDER: S-EPMC6861275 | biostudies-literature | 2019 Nov

REPOSITORIES: biostudies-literature

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Pauli-limit upper critical field of high-temperature superconductor La1.84Sr0.16CuO4.

Nakamura Daisuke D Adachi Tadashi T Omori Keisuke K Koike Yoji Y Takeyama Shojiro S

Scientific reports 20191118 1

The upper critical field of a cuprate high-temperature superconductor, La1.84Sr0.16CuO4, was investigated by high-frequency self-resonant contactless electrical conductivity measurements in magnetic fields up to 102 T. An irreversible transition was observed at 85 T (T = 4.2 K), defined as the upper critical field. The temperature-dependent upper critical field was argued on the basis of the Werthamer-Helfand-Hohenberg theory. The Pauli-limiting pair-breaking pro ...[more]

PMID: 31740679

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