Constructing the Fulde-Ferrell-Larkin-Ovchinnikov state in antiferromagnetic insulator CrOCl
Abstract
Time reversal symmetry breaking in superconductors, resulting from external magnetic fields or spontaneous magnetization, often leads to unconventional superconducting properties. In this way, a conventional Fulde-Ferrell-Larkin-Ovchinnikov (FFLO) state, characterized by the Cooper pairs with nonzero total momentum, may be realized by the Zeeman effect caused from external magnetic fields. Here, we report the observation of superconductivity in a few-layer antiferromagnetic insulator CrOCl by utilizing superconducting proximity effect with NbSe2 flakes. The superconductivity demonstrates a considerably weak gap of about 0.12 meV and the in-plane upper critical field reveals as behavior of the FFLO state at low temperature. Our first-principles calculations indicate that the proximitized superconductivity may exist in the CrOCl layer with Cr vacancies or line-defects. Moreover, the FFLO state could be induced by the inherent larger spin splitting in the CrOCl layer. Our findings not only demonstrate the fascinating interaction between superconductivity and magnetism, but also provide a possible path to construct FFLO state by intrinsic time reversal symmetry breaking and superconducting proximity effect.
Keywords
Cite
@article{arxiv.2311.00266,
title = {Constructing the Fulde-Ferrell-Larkin-Ovchinnikov state in antiferromagnetic insulator CrOCl},
author = {Yifan Ding and Jiadian He and Shihao Zhang and Huakun Zuo and Pingfan Gu and Jiliang Cai and Xiaohui Zeng and Pu Yan and Kecheng Cao and Kenji Watanabe and Takashi Taniguchi and Peng Dong and Yiwen Zhang and Yueshen Wu and Xiang Zhou and Jinghui Wang and Yulin Chen and Yu Ye and Jianpeng Liu and Jun Li},
journal= {arXiv preprint arXiv:2311.00266},
year = {2024}
}