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Anisotropic Superconducting Properties of MgB2 Single Crystals

Yu. Eltsev·S. Lee·K. Nakao·N. Chikumoto·S. Tajima·N. Koshizuka·M. Murakami
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Abstract

In-plane electrical transport properties of MgB2 single crystals grown under high pressure of 4-6 GPa and temperature of 1400-1700oC in Mg-B-N system have been measured. For all specimens we found sharp superconducting transition around 38.1-38.3K with transition width within 0.2-0.3K. Estimated resistivity value at 40K is about 1 mkOhmcm and resistivity ratio R(273K)/R(40K) of about 4.9. Results of measurements in magnetic field up to 5.5T perpendicular to Mg and B planes and up to 9T in parallel orientation show temperature dependent anisotropy of the upper critical field with anisotropy ratio increasing from 2.2 close to Tc up to about 3 below 30K. Strong deviation of the angular dependence of Hc2 from anisotropic mass model has been also found.

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Yu. Eltsev, S. Lee, K. Nakao, N. Chikumoto, S. Tajima, N. Koshizuka, M. Murakami. 2002-02-08. Anisotropic Superconducting Properties of MgB2 Single Crystals. https://doi.org/10.1016/s0921-4534(02)01383-7

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