Boron quantum dots all-optical modulator based on efficient photothermal effect
Cong Wang, Qianyuan Chen, Hualong Chen, Jun Liu, Yufeng Song, Jie Liu, Delong Li, Yanqi Ge, Youning Gong, Yupeng Zhang, Han Zhang
Abstract
All-optical devices without external electronic components have drawn extraordinary attentions in all-optical communication. In this work, boron quantum dots (BQDs) were synthesized by a facile liquid-phase exfoliation method. The as-prepared BQDs showed good structural homogeneity and crystallinity, broadband optical absorption as well as excellent photothermal properties. Femtosecond-resolved transient absorption further revealed the short carrier relaxation time of BQDs. Inspired by the outstanding photothermal properties and ultrafast carrier dynamic of BQDs, we fabricated BQDsbased all-optical modulator. The phase shift with a slope efficiency of 0.032 /mW and response time of 0.97 ms can be achieved. The modulator was used in laser resonance cavity to achieve all-optical actively Q-switched laser operation with control repetition rate. This prototypical BQDs-based all-optical modulator shows a great potential to be applied in all-optical information processing and communication.