Upper Critical Field, Critical Current Density and Activation Energy of the New La1-xSmxO0.5F0.5BiS2 (x=0.2, 0.8) Superconductors

作者：Selvan Ganesan Kalai; Thakur Gohil Singh; Manikandan Krishnan; Uwatoko Yoshia; Haque Zeba; Gupta Laxmi Chand; Ganguli Ashok Kumar; Arumugam Sonachalam

来源：Journal of the Physical Society of Japan, 2015, 84(12): 124701.

DOI：10.7566/JPSJ.84.124701

Critical current density (J(c)), thermal activation energy (U-0), and upper critical field (H-c2) of La1-xSmxO0.5F0.5BiS2 (x = 0.2, 0.8) superconductors are investigated from magnetic field dependent rho(T) studies. The estimated upper critical field (H-c2) 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 (J(c)) is estimated to be 1.35 x 10(5) and 5.07 x 10(5) A/cm(2) (2 K) for x = 0.2 and 0.8 respectively, using the Bean's model. The thermal activation energy (U-0/k(B)) is 61K for x = 0.2 and 140K 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.

• 出版日期2015-12-15