High-Temperature Anomalous Metal States in Iron-Based Interface Superconductors

Yanan Li; Haiwen Liu; Haoran Ji; Chengcheng Ji; Shichao Qi; Xiaotong Jiao; Wenfeng Dong; Yi Sun; Wenhao Zhang; Zihan Cui; Minghu Pan; Nitin Samarth; Lili Wang; X. C. Xie; Qi-Kun Xue; Yi Liu; Jian Wang

doi:10.1103/physrevlett.132.226003

arXiv · 2111.15488

High-Temperature Anomalous Metal States in Iron-Based Interface Superconductors

Yanan Li·Haiwen Liu·Haoran Ji·Chengcheng Ji·Shichao Qi·Xiaotong Jiao·Wenfeng Dong·Yi Sun·Wenhao Zhang·Zihan Cui·Minghu Pan·Nitin Samarth·Lili Wang·X. C. Xie·Qi-Kun Xue·Yi Liu·Jian Wang

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Abstract

The nature of the anomalous metal state has been a major puzzle in condensed matter physics for more than three decades. Here, we report systematic investigation and modulation of the anomalous metal states in high-temperature interface superconductor FeSe films on SrTiO3 substrate. Remarkably, under zero magnetic field, the anomalous metal state persists up to 20 K in pristine FeSe films, an exceptionally high temperature standing out from previous observations. In stark contrast, for the FeSe films with nano-hole arrays, the characteristic temperature of the anomalous metal state is considerably reduced. We demonstrate that the observed anomalous metal states originate from the quantum tunneling of vortices adjusted by the Ohmic dissipation. Our work offers a perspective for understanding the origin and modulation of the anomalous metal states in two-dimensional bosonic systems.

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Yanan Li, Haiwen Liu, Haoran Ji, Chengcheng Ji, Shichao Qi, Xiaotong Jiao, Wenfeng Dong, Yi Sun, Wenhao Zhang, Zihan Cui, Minghu Pan, Nitin Samarth, Lili Wang, X. C. Xie, Qi-Kun Xue, Yi Liu, Jian Wang. 2021-11-30. High-Temperature Anomalous Metal States in Iron-Based Interface Superconductors. https://doi.org/10.1103/physrevlett.132.226003

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