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arXiv · 2212.02022

Quasi two-dimensional nature of high-Tc superconductivity in iron-based (Li,Fe)OHFeSe

Dong Li·Yue Liu·Zouyouwei Lu·Peiling Li·Yuhang Zhang·Sheng Ma·Jiali Liu·Jihu Lu·Hua Zhang·Guangtong Liu·Fang Zhou·Xiaoli Dong·Zhongxian Zhao
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Abstract

The intercalated iron selenide (Li,Fe)OHFeSe has a strongly layered structure analogous to the quasi two-dimensional (2D) bismuth cuprate superconductors, and exhibits both high-temperature (Tc) and topological superconductivity. However, the issue of its superconductivity dimensionality has not yet been fully investigated so far. Here we report that the quasi-2D superconductivity features, including the high anisotropy γ = 151 and the associated quasi-2D vortices, are also revealed for (Li,Fe)OHFeSe, based on systematic experiments of the electrical transport and magnetization and model fittings. Thus, we establish a new vortex phase diagram for (Li,Fe)OHFeSe, which delineates an emergent quasi-2D vortex-liquid state, and a subsequent vortex-solid dimensional crossover from a pancake-like to a three-dimensional state with decreasing temperature and magnetic field. Furthermore, we find that all the quasi-2D characteristics revealed here for the high-Tc iron selenide superconductor are very similar to those reported for the high-Tc bismuth cuprate superconductors.

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Dong Li, Yue Liu, Zouyouwei Lu, Peiling Li, Yuhang Zhang, Sheng Ma, Jiali Liu, Jihu Lu, Hua Zhang, Guangtong Liu, Fang Zhou, Xiaoli Dong, Zhongxian Zhao. 2022-12-05. Quasi two-dimensional nature of high-Tc superconductivity in iron-based (Li,Fe)OHFeSe. https://doi.org/10.1088/0256-307x%2F39%2F12%2F127402

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