Possible Evidence for Berezinskii-Kosterlitz-Thouless Transition in Ba(Fe0.914Co0.086)2As2 Crystals

Wen-He Jiao; Xiao-Feng Xu; Hao Jiang; Zhu-An Xu; Qing-Hu Chen; Guang-Han Cao

doi:10.3390/ma14216294

Possible Evidence for Berezinskii-Kosterlitz-Thouless Transition in Ba(Fe_0.914Co_0.086)₂As₂ Crystals

Materials (Basel). 2021 Oct 22;14(21):6294. doi: 10.3390/ma14216294.

Authors

Wen-He Jiao^{1

2}, Xiao-Feng Xu³, Hao Jiang⁴, Zhu-An Xu¹, Qing-Hu Chen¹, Guang-Han Cao¹

Affiliations

¹ Interdisciplinary Center for Quantum Information, Zhejiang Province Key Laboratory of Quantum Technology and Devices, Department of Physics, Zhejiang University, Hangzhou 310027, China.
² Ningbo Institute of Materials Technology and Engineering, Chinese Academy of Sciences, Ningbo 315201, China.
³ Department of Applied Physics, Zhejiang University of Technology, Hangzhou 310023, China.
⁴ School of Physics and Optoelectronics, Xiangtan University, Xiangtan 411105, China.

Abstract

In this study, we measure the in-plane transport properties of high-quality Ba(Fe_0.914Co_0.086)₂As₂ single crystals. Signatures of vortex unbinding Berezinskii-Kosterlitz-Thouless (BKT) transition are shown from both the conventional approach and the Fisher-Fisher-Huse dynamic scaling analysis, in which a characteristic Nelson-Kosterlitz jump is demonstrated. We also observe a non-Hall transverse signal exactly at the superconducting transition, which is explained in terms of guided motion of unbound vortices.

Keywords: Berezinskii–Kosterlitz–Thouless transition; superconducting transition; vortices.

Abstract

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