Giant room-temperature nonlinearities in a monolayer Janus topological semiconductor
Abstract
Nonlinear optical materials possess wide applications, ranging from terahertz and mid-infrared detection to energy harvesting. Recently, the correlations between nonlinear optical responses and certain topological properties, such as the Berry curvature and the quantum metric tensor, have attracted considerable interest. Here, we report giant room-temperature nonlinearities in non-centrosymmetric two-dimensional topological materials—the Janus transition metal dichalcogenides in the 1 T’ phase, synthesized by an advanced atomic-layer substitution method. High harmonic generation, terahertz emission spectroscopy, and second harmonic generation measurements consistently show orders-of-the-magnitude enhancement in terahertz-frequency nonlinearities in 1 T’ MoSSe (e.g., > 50 times higher than 2H MoS2 for 18th order harmonic generation; > 20 times higher than 2H MoS2 for terahertz emission). We link this giant nonlinear optical response to topological band mixing and strong inversion symmetry breaking due to the Janus structure. Our work defines general protocols for designing materials with large nonlinearities and heralds the applications of topological materials in optoelectronics down to the monolayer limit.
Document Details
- Document Type
- Pub Defense Publication
- Publication Date
- Aug 16, 2023
- Source ID
- 10.1038/s41467-023-40373-z
Entities
People
- Aaron M Lindenberg
- Amalya C. Johnson
- Changan Huangfu
- Chenyi Xia
- Christian Heide
- Enzheng Shi
- Fang Liu
- Felipe de Quesada
- Haowei Xu
- Hongzhi Shen
- Jiaojian Shi
- Jing Kong
- Ju Li
- Leo Yu
- Liying Jiao
- Shambhu Ghimire
- Tianyi Zhang
- Tony Heinz
- Yunfan Guo
Organizations
- National Natural Science Foundation of China
- Office of Naval Research
- United States Department of Energy
- Zhejiang University