Energy transfer driven brightening of MoS2 by ultrafast polariton relaxation in microcavity MoS2/hBN/WS2 heterostructures

• Main Authors: Hu, Zehua, Krisnanda, Tanjung, Fieramosca, Antonio, Zhao, Jiaxin, Sun, Qianlu, Chen, Yuzhong, Liu, Haiyun, Luo, Yuan, Su, Rui, Wang, Junyong, Watanabe, Kenji, Taniguchi, Takashi, Eda, Goki, Wang, Renshaw Xiao, Ghosh, Sanjib, Dini, Kevin, Sanvitto, Daniele, Liew, Timothy Chi Hin, Xiong, Qihua
• Other Authors: School of Physical and Mathematical Sciences
• Format: Article
• Language: English
• Published: 2024
• Subjects: Physics; Energy transfer; Photoluminescence
• Online Access: https://hdl.handle.net/10356/174689
• Institution: Nanyang Technological University

Energy transfer is a ubiquitous phenomenon that delivers energy from a blue-shifted emitter to a red-shifted absorber, facilitating wide photonic applications. Two-dimensional (2D) semiconductors provide unique opportunities for exploring novel energy transfer mechanisms in the atomic-scale limit. Herein, we have designed a planar optical microcavity-confined MoS2/hBN/WS2 heterojunction, which realizes the strong coupling among donor exciton, acceptor exciton, and cavity photon mode. This configuration demonstrates an unconventional energy transfer via polariton relaxation, brightening MoS2 with a record-high enhancement factor of ~440, i.e., two-order-of-magnitude higher than the data reported to date. The polariton relaxation features a short characteristic time of ~1.3 ps, resulting from the significantly enhanced intra- and inter-branch exciton-exciton scattering. The polariton relaxation dynamics is associated with Rabi energies in a phase diagram by combining experimental and theoretical results. This study opens a new direction of microcavity 2D semiconductor heterojunctions for high-brightness polaritonic light sources and ultrafast polariton carrier dynamics.