Charge density wave (CDW is one of the most ubiquitous electronic orders in quantum materials. While the essential ingredients of CDW order have been extensively studied, a comprehensive microscopic understanding is yet to be reached. Recent research efforts on the CDW phenomena in two-dimensional (2D) materials provide a new pathway toward a deeper understanding of its complexity. This review provides an overview of the CDW orders in 2D with atomically thin transition metal dichalcogenides (TMDCs) as the materials platform. We mainly focus on the electronic structure investigations on the epitaxially grown TMDC samples with angle-resolved photoemission spectroscopy and scanning tunneling microscopy/spectroscopy as complementary experimental tools. We discuss the possible origins of the 2D CDW, novel quantum states coexisting with them, and exotic types of charge orders that can only be realized in the 2D limit.

中文翻译：

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二维过渡金属二硫属化物中的电荷密度波

电荷密度波（CDW）是量子材料中最普遍的电子秩序之一。虽然CDW秩序的基本成分已被广泛研究，但尚未达到全面的微观理解。最近对二维CDW现象的研究工作(2D) 材料为更深入地了解其复杂性提供了一条新途径。本综述概述了以原子薄过渡金属二硫属化物 (TMDC) 作为材料平台的电子结构研究。我们讨论了 2D CDW 的可能起源、与其共存的新型量子态以及只能实现的奇异电荷顺序类型。在二维极限内。