Emergent quantum state unveiled by ultrafast collective dynamics in 1T-TaS2

• 成果类型: Article
• 署名作者: Hasaien, Jiazila; Wu, Yanling; Shi, Mengzhu; Zhai, Yanni; Wu, Qiong; Liu, Zheng; Zhou, Yi; Chen, Xianhui; Zhao, Jimin
• 署名单位: Chinese Academy of Sciences; Institute of Physics, CAS; Chinese Academy of Sciences; University of Chinese Academy of Sciences, CAS; Chinese Academy of Sciences; University of Science & Technology of China, CAS; Tsinghua University; Songshan Lake Materials Laboratory
• 刊物名称: PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA
• ISSN/ISSBN: 0027-8513
• DOI: 10.1073/pnas.2406464122
• 发表日期: 2025-03-04
• 关键词: charge; generation; waves

摘要

Charge density wave (CDW) material 1T- TaS2 was proposed as a quantum spin liquid candidate, on which a cluster Mott insulator comes into being below the transition temperature. We report an experimental ultrafast generation and detection of the coherent amplitude mode (AM) of its CDW state. A salient feature emerges: The coherent CDW mode AM exhibits an unusual T3.56 temperature dependence below 65 K, in addition to the T2 temperature dependence observed in the 65 to 200 K range. This behavior suggests the enhancement of in- gap electronic excitations below 65 K and the emergence of a new phase of matter. Consequently, the intriguing quantum state leads to a crossover. Our investigation provides insights into understanding the interplay among various degrees of freedom in quantum materials.