Interlayer Charge-density-wave Vector Phase Induced Structural Chirality

Sen Shao; Wei-Chi Chiu; Tao Hou; Naizhou Wang; Ilya Belopolski; Yilin Zhao; Jinyang Ni; Qi Zhang; Yongkai Li; Jinjin Liu; Mohammad Yahyavi; Yuanjun Jin; Qiange Feng; Peiyuan Cui; Cheng-Long Zhang; Yugui Yao; Zhiwei Wang; Jia-Xin Yin; Su-Yang Xu; Qiong Ma; Wei-bo Gao; Md Shafayat Hossain; Arun Bansil; Guoqing Chang

arXiv · 2411.03664

Interlayer Charge-density-wave Vector Phase Induced Structural Chirality

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Abstract

Chiral charge density waves (CDWs) have attracted intense interest due to their exotic quantum properties, yet the microscopic origin of structural chirality emerging from correlated charge order remains elusive. Here, we reveal that the interlayer phases of CDW wave vectors, an overlooked degree of freedom, play a crucial role in driving chiral structural displacements in layered CDW materials. By explicitly incorporating the interlayer phases in first-principles calculations, we successfully obtained the chiral structure of the CDW phases of AV$_3$Sb$_5$ (A= K, Rb, and Cs) and 1T-TiSe$_2$. The electronic and optical properties of the predicted chiral structures are consistent with experimental measurements of these materials in their CDW phases. We further predict that 1T-NbSe$_2$ is a promising material candidate for realizing chiral CDW order. Beyond materials prediction, our theory reveals that the chiral CDW can be manipulated by electron filling. Our study opens new avenues for discovering, designing, and engineering chiral CDW materials.

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Sen Shao, Wei-Chi Chiu, Tao Hou, Naizhou Wang, Ilya Belopolski, Yilin Zhao, Jinyang Ni, Qi Zhang, Yongkai Li, Jinjin Liu, Mohammad Yahyavi, Yuanjun Jin, Qiange Feng, Peiyuan Cui, Cheng-Long Zhang, Yugui Yao, Zhiwei Wang, Jia-Xin Yin, Su-Yang Xu, Qiong Ma, Wei-bo Gao, Md Shafayat Hossain, Arun Bansil, Guoqing Chang. 2024-11-06. Interlayer Charge-density-wave Vector Phase Induced Structural Chirality. https://arxiv.org/abs/2411.03664

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