Fluctuation conductivity of single-crystalline BaFe1.8 Co0.2As2 in the critical region

Authors

Soo Hyun Kim, Dept of Physics Sogang University Seoul
Changho Choi, Dept Physics Sogang University Republic Korea
Myung-Hwa Jung, Sogang University, South Korea
Jung-Bum Yoon, Nano Materials Research Team Korea
Young-Hun Jo, Nano Materials Research Team Korea
Xiaolin Wang, University of WollongongFollow
X.H Chen, Hefei National Laboratory China
X.F Wang, University of Science & Technology China
Sung-Ik Lee, Sogang University, South Korea
Ki-Young Choi, Sogang University Seoul

RIS ID

33976

Publication Details

Kim, S, Choi, C, Jung, M, Yoon, J, Jo, Y, Wang, X, Chen, X, Wang, XL, Lee, S & Choi, K (2010), Fluctuation conductivity of single-crystalline BaFe1.8 Co0.2As2 in the critical region, Journal of Applied Physics, 108(6), pp. 063916-1-063916-4.

Abstract

The magnetofluctuation conductivity, called excess conductivity, originated from the forming of the superconducting droplet near to the mean-field transition temperature, was measured for the optimally doped BaFe_1.8Co_0.2As₂ single crystals with a critical temperature, T_c, of 24.6 K. This measurement of the excess conductivity for magnetic fields up to 9 T was compared with the thermodynamic scaling theory in the critical region, in which not only the Gaussian fluctuation but also fourth order terms of the order parameter are included. An analysis of the excess conductivity showed that the superconductivity followed three-dimensional scaling rather than two-dimensional scaling even though the sample had a layered structure.