近日，美国卡耐基梅隆大学Shi, Su-Fei团队揭示了三层摩尔超晶格中强相互作用驱动的四极到偶极激子跃迁。该项研究成果发表在2025年8月21日出版的《自然—光子学》杂志上。
过渡金属二硫族化合物的三层摩尔超晶格中额外的层自由度使新的激子物种，如四极激子的出现成为可能，它们表现出独特的激子相互作用，并有望实现有趣的激子相及其量子相变。同时，Mott绝缘体和广义Wigner晶体的观察结果表明，在莫尔
研究组证明了强激子-激子和电子-激子相互作用，都源于robthemt电子相关，可以用来控制驱动四极和偶极激子之间的跃迁。这是通过调整三层半导体莫尔晶格中的激子密度或静电掺杂来实现的。该发现不仅促进了对四极激子的基本理解，而且还为探索和工程多体量子现象开辟了新的途径，通过半导体莫尔系统中的新型相关激子。
附：英文原文
Title: Strong-interaction-driven quadrupolar-to-dipolar exciton transitions in a trilayer moiré superlattice
Author: Meng, Yuze, Ma, Lei, Yan, Li, Khalifa, Ahmed, Chen, Dongxue, Zhang, Shuai, Banerjee, Rounak, Taniguchi, Takashi, Watanabe, Kenji, Tongay, Seth Ariel, Hunt, Benjamin, Lin, Shi-Zeng, Yao, Wang, Cui, Yong-Tao, Chatterjee, Shubhayu, Shi, Su-Fei
Issue&Volume: 2025-08-21
Abstract: The additional layer degree of freedom in trilayer moiré superlattices of transition metal dichalcogenides enables the emergence of novel excitonic species, such as quadrupolar excitons, which exhibit unique excitonic interactions and hold promise for realizing intriguing excitonic phases and their quantum phase transitions. Concurrently, the presence of strong electronic correlations in moiré superlattices, as exemplified by the observations of Mott insulators and generalized Wigner crystals, offers a direct route to manipulate these new excitonic states and the resulting collective excitonic phases. Here we demonstrate that strong exciton–exciton and electron–exciton interactions, both stemming from robust electron correlations, can be harnessed to controllably drive transitions between quadrupolar and dipolar excitons. This is achieved by tuning either the exciton density or electrostatic doping in a trilayer semiconducting moiré superlattice. Our findings not only advance the fundamental understanding of quadrupolar excitons but also usher in new avenues for exploring and engineering many-body quantum phenomena through novel correlated excitons in semiconducting moiré systems.
DOI: 10.1038/s41566-025-01741-x
Source: https://www.nature.com/articles/s41566-025-01741-x