Solid- state high harmonic spectroscopy for all- optical band structure probing of high- pressure quantum states

• 成果类型: Article
• 署名作者: Hu, Shi-Qi; Chen, Da-Qiang; Du, Lan-Lin; Meng, Sheng
• 署名单位: Chinese Academy of Sciences; Chinese Academy of Sciences; Institute of Physics, CAS; Chinese Academy of Sciences; University of Chinese Academy of Sciences, CAS; Songshan Lake Materials Laboratory
• 刊物名称: PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA
• ISSN/ISSBN: 0027-12628
• DOI: 10.1073/pnas.2316775121
• 发表日期: 2024-02-06
• 关键词: superconductivity; generation; electrons; hydride

摘要

High pressure has triggered various novel states/properties in condensed matter, as the most representative and dramatic example being near- room- temperature superconductivity in highly pressured hydrides (-200 GPa). However, the mechanism of superconductivity is not confirmed, due to the lacking of effective approach to probe the electronic band structure under such high pressures. Here, we theoretically propose that the band structure and electron- phonon coupling (EPC) of high- pressure quantum states can be probed by solid - state high harmonic generation (sHHG). This strategy is investigated in high- pressure Im-3m H3S by the state - of - the - art first- principles time- dependent density- functional theory simulations, where the sHHG is revealed to be strongly dependent on the electronic structures and EPC. The dispersion of multiple bands near the Fermi level is effectively retrieved along different momentum directions. Our study provides unique insights into the potential all- optical route for band structure and EPC probing of high- pressure quantum states, which is expected to be helpful for the experimental exploration of high- pressure superconductivity in the future.