Visualization of Chiral Electronic Structure and Anomalous Optical Response in a Material with Chiral Charge Density Waves

Year: 2022

Type: article

Abstract: Chiral materials have attracted significant research interests as they exhibit intriguing physical properties, such as chiral optical response, spin-momentum locking, and chiral induced spin selectivity. Recently, layered transition metal dichalcogenide 1T-TaS_{2} has been found to host a chiral charge density wave (CDW) order. Nevertheless, the physical consequences of the chiral order, for example, in electronic structures and the optical properties, are yet to be explored. Here, we report the spectroscopic visualization of an emergent chiral electronic band structure in the CDW phase, characterized by windmill-shaped Fermi surfaces. We uncover a remarkable chirality-dependent circularly polarized Raman response due to the salient in-plane chiral symmetry of CDW, although the ordinary circular dichroism vanishes. Chiral Fermi surfaces and anomalous Raman responses coincide with the CDW transition, proving their lattice origin. Our Letter paves a path to manipulate the chiral electronic and optical properties in two-dimensional materials and explore applications in polarization optics and spintronics.

Source: Physical Review Letters

DOI: 10.1103/physrevlett.129.156401

Authors: H. F. Yang, K. Y. He, J. Koo, S. W. Shen, S. H. Zhang, G. Liu, Y. Z. Liu, C. Chen, A. J. Liang, K. Huang, M. X. Wang, J. J. Gao, X. Luo, L. X. Yang, J. P. Liu, Y. P. Sun, S. C. Yan, B. H. Yan, Y. L. Chen, X. Xi, Z. K. Liu

Institutions: ShanghaiTech University, National Laboratory of Solid State Microstructures, Nanjing University, Weizmann Institute of Science, University of Oxford, Chinese Academy of Sciences, Institute of Solid State Physics, State Key Laboratory of Low-Dimensional Quantum Physics, Tsinghua University, High Magnetic Field Laboratory, Collaborative Innovation Center of Advanced Microstructures

Language: English

Topic: Topological Materials and Phenomena

Subfield: Condensed Matter Physics

Field: Physics and Astronomy

Domain: Physical Sciences

Open Access status: green

Funders: Minerva Foundation, National Natural Science Foundation of China, Bundesministerium für Bildung und Forschung, Chinese Academy of Sciences, Science and Technology Commission of Shanghai Municipality, ShanghaiTech University, National Synchrotron Radiation Laboratory, Office of Science, Hefei Science Center, Chinese Academy of Sciences, National Key Research and Development Program of China, Key Research Program of Frontier Science, Chinese Academy of Sciences, H2020 European Research Council, Advanced Light Source

OpenAlex ID: W4281258366