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arXiv · 1407.1357

Superconductivity of 2.2 K under Pressure in Helimagnet CrAs

Hisashi Kotegawa·Shingo Nakahara·Hideki Tou·Hitoshi Sugawara
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Abstract

We report resistivity measurements of the helimagnet CrAs under pressures. The helimagnetic transition with T_N ~ 265 K at ambient pressure is completely suppressed above a critical pressure of P_c ~ 0.7 GPa, and superconductivity is observed at ~2.2 K for zero resistance, which exists in a wide pressure range extending beyond 3 GPa. Both the upper critical field H_{c2} and the coefficient A in the resistivity increase toward P_c, suggesting that the superconductivity of CrAs is mediated by electronic correlations enhanced in the vicinity of the helimagnetic phase.

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Hisashi Kotegawa, Shingo Nakahara, Hideki Tou, Hitoshi Sugawara. 2014-07-05. Superconductivity of 2.2 K under Pressure in Helimagnet CrAs. https://doi.org/10.7566/jpsj.83.093702

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