Charge Density Waves in the 2.5-Dimensional Quantum Heterostructure

F. Z. Yang; T. T. Zhang; F. Y. Meng; H. C. Lei; C. Nelson; Y. Q. Cai; E. Vescovo; A. H. Said; P Mercado Lozano; G. Fabbris; H. Miao

doi:10.1103/physrevb.111.l041101

arXiv · 2407.14661

Charge Density Waves in the 2.5-Dimensional Quantum Heterostructure

F. Z. Yang·T. T. Zhang·F. Y. Meng·H. C. Lei·C. Nelson·Y. Q. Cai·E. Vescovo·A. H. Said·P Mercado Lozano·G. Fabbris·H. Miao

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Abstract

Charge density wave (CDW) and their interplay with correlated and topological quantum states are forefront of condensed matter research. The 4$H_{b}$-TaS$_2$ is a CDW ordered quantum heterostructure that is formed by alternative stacking of Mott insulating 1T-TaS$_2$ and Ising superconducting 1H-TaS$_2$. While the $\sqrt{13}\times\sqrt{13}$ and 3$\times$3 CDWs have been respectively observed in the bulk 1T-TaS$_2$ and 2H-TaS$_2$, the CDWs and their pivotal role for unconventional superconductivity in the 4$H_{b}$-TaS$_2$ remain unsolved. In this letter, we reveal the 2-dimensional (2D) $\sqrt{13}\times\sqrt{13}$ chiral CDW in the 1T-layers and intra-unit cell coupled 2D 2$\times$2 CDW in the 1H and 1H' layers of 4$H_{b}$-TaS$_2$. Our results establish 4$H_{b}$-TaS$_2$ a novel 2.5D quantum heterostructure, where 2D quantum states emerge from 3D crystalline structure.

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F. Z. Yang, T. T. Zhang, F. Y. Meng, H. C. Lei, C. Nelson, Y. Q. Cai, E. Vescovo, A. H. Said, P Mercado Lozano, G. Fabbris, H. Miao. 2024-07-19. Charge Density Waves in the 2.5-Dimensional Quantum Heterostructure. https://doi.org/10.1103/physrevb.111.l041101

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