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Magnetic Determination of $H_{c2}$ under Accurate Alignment in (TMTSF)$_2$ClO$_4$

J. I. Oh·M. J. Naughton
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Abstract

Cantilever magnetometry has been used to measure the upper critical magnetic field $H_{c2}$ of the quasi-one dimensional molecular organic superconductor (TMTSF)$_2$ClO$_4$. From simultaneous resistivity and torque magnetization experiments conducted under precise field alignment, $H_{c2}$ at low temperature is shown to reach 5T, nearly twice the Pauli paramagnetic limit imposed on spin singlet superconductors. These results constitute the first thermodynamic evidence for a large $H_{c2}$ in this system and provide support for spin triplet pairing in this unconventional superconductor

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J. I. Oh, M. J. Naughton. 2004-01-29. Magnetic Determination of $H_{c2}$ under Accurate Alignment in (TMTSF)$_2$ClO$_4$. https://doi.org/10.1103/physrevlett.92.067001

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