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Superconducting properties of well-shaped MgB2 single crystal

Kijoon H. P. Kim·Jae-Hyuk Choi·C. U. Jung·P. Chowdhury·Min-Seok Park·Heon-Jung Kim·J. Y. Kim·Zhonglian Du·Eun-Mi Choi·Mun-Seog Kim·W. N. Kang·Sung-Ik Lee·Gun Yong Sung·Jeong Yong Lee
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Abstract

We report measurements of the transport and the magnetic properties of high-quality, sub-millimeter-sized MgB2 single crystals with clear hexagonal-plate shapes. The low-field magnetization and the magnetic hysteresis curves show the vortex pinning of these crystals to be very weak. The Debye temperature of $Θ_{D}\sim 1100$ K, obtained from the zero-field resistance curve, suggests that the normal-state transport properties are dominated by electron-phonon interactions. The resistivity ratio between 40 K and 300 K was about 5, and the upper critical field anisotropy ratio was 3 $\pm$ 0.2 at temperatures around 32 K.

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Kijoon H. P. Kim, Jae-Hyuk Choi, C. U. Jung, P. Chowdhury, Min-Seok Park, Heon-Jung Kim, J. Y. Kim, Zhonglian Du, Eun-Mi Choi, Mun-Seog Kim, W. N. Kang, Sung-Ik Lee, Gun Yong Sung, Jeong Yong Lee. 2001-06-22. Superconducting properties of well-shaped MgB2 single crystal. https://doi.org/10.1103/physrevb.65.100510

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