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arXiv · 2301.02037

In-situ electrical and thermal transport properties of FeySe1-xTex films with ionic liquid gating

Juan Xu·Mingyang Qin·Zefeng Lin·Xu Zhang·Ruozhou Zhang·Li Xu·Liping Zhang·Qiuyan Shi·Jie Yuan·Beiyi Zhu·Chao Dong·Rui Xiong·Qihong Chen·Yangmu Li·Jing Shi·Kui Jin
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Abstract

We combine in-situ electrical transport and Seebeck coefficient measurements with the ionic liquid gating technique to investigate superconductivity and the normal state of FeySe1-xTex (FST) films. We find that the pristine FST films feature a non-Fermi liquid temperature dependence of the Seebeck coefficient, i.e., S/T ~ AS lnT, and AS is strongly correlated with the superconducting transition temperature (Tc). Ionic liquid gating significantly raises Tc of FST films, for which the Seebeck coefficient displays a novel scaling behavior and retains the logarithmic temperature dependence. Moreover, a quantitative relationship between the slope of T-linear resistivity (A\r{ho}) and Tc for gated films is observed, i.e., (A\r{ho})1/2 ~ Tc, consistent with previous reports on cuprates and FeSe. The scaling behaviors of AS and A\r{ho} point to a spin-fluctuation-associated transport mechanism in gated FeySe1-xTex superconductors.

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Juan Xu, Mingyang Qin, Zefeng Lin, Xu Zhang, Ruozhou Zhang, Li Xu, Liping Zhang, Qiuyan Shi, Jie Yuan, Beiyi Zhu, Chao Dong, Rui Xiong, Qihong Chen, Yangmu Li, Jing Shi, Kui Jin. 2023-01-05. In-situ electrical and thermal transport properties of FeySe1-xTex films with ionic liquid gating. https://doi.org/10.1103/physrevb.107.094514

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