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arXiv · 1507.06247

Upper critical field, critical current density and activation energy of the new La1-xSmxOF0.5BiS2 (x = 0.2, 0.8) superconductor

G. Kalai Selvan·G. S. Thakur·K. Manikandan·Y. Uwatoko·Zeba Haque·L. C. Gupta·A. K. Ganguli·S. Arumugam
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Abstract

Critical current density (Jc), thermal activation energy (U0), and upper critical field (Hc2) of La1-xSmxO0.5F0.5BiS2 (x = 0.2, 0.8) superconductors are investigated from magnetic field dependent \r{ho}(T) studies. The estimated upper critical field (Hc2) has low values of 1.04 T for x = 0.2 and 1.41 T for x = 0.8. These values are lower than Sm free LaO0.5F0.5BiS2 superconductor (1.9 T). The critical current density (Jc) is estimated to be 1.35*105 A/cm2 and 5.07 *105 A/cm2 (2 K) for x = 0.2 and 0.8 respectively, using the Bean's model. The thermal activation energy (U0/kB) is 61 K for x = 0.2 and 140 K for x =0.8 as calculated from Arrhenius plots at low magnetic field (1 T) and indicates a strong flux pinning potential which might be co-existing with applied magnetic field.

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G. Kalai Selvan, G. S. Thakur, K. Manikandan, Y. Uwatoko, Zeba Haque, L. C. Gupta, A. K. Ganguli, S. Arumugam. 2015-07-22. Upper critical field, critical current density and activation energy of the new La1-xSmxOF0.5BiS2 (x = 0.2, 0.8) superconductor. https://arxiv.org/abs/1507.06247

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