Giant Second Harmonic Generation by Photoinduced Phase Engineering
Addressing the growing demand for ever-shrinking nonlinear optical devices requires a paradigm shift to two-dimensional (2D) materials to bypass phase-matching limitations encountered in bulk crystals. While strategies like strain, electrical gating, and surface decoration have been explored to enhance the nonlinear susceptibility of 2D materials, the potential of laser-driven effects, with its exceptional controllability and accessibility, remains largely underexplored. Here, we demonstrate an optical approach to achieve a giant second-order parametric response in a metastable noncentrosymmetric 1M-WS<sub>2</sub> by selectively controlling laser pulse duration. We report a record effective second harmonic generation coefficient of ∼2000 pm/V, surpassing typical values of conventional nonlinear crystals by several orders of magnitude. Detailed analyses reveal that the structural distortions unique to the 1M phase are crucial for the enhanced nonlinear response. These findings establish an alternative way to amplify nonlinear optical properties and set 1M-WS<sub>2</sub> as a promising candidate for compact optical modulators and nanolasers.
Authors
- Tianping Ying (ORCID: https://orcid.org/0000-0001-7665-1270)
- Jiahao Yan (ORCID: https://orcid.org/0000-0002-3333-0669)
- Yunyun Dai (ORCID: https://orcid.org/0000-0002-1186-1864)
- Jiangang Guo (ORCID: https://orcid.org/0000-0003-3880-3012)
- Boqin Song (ORCID: https://orcid.org/0009-0007-3323-8583)
- Luojun Du (ORCID: https://orcid.org/0000-0002-2420-8258)
- Tongtong Xue
- Xinyue Li (ORCID: https://orcid.org/0000-0001-5370-021X)
- Xiaolong Chen (ORCID: https://orcid.org/0000-0001-8455-2117)
- Jing Chen (ORCID: https://orcid.org/0000-0001-7358-4949)
- Sheng Meng (ORCID: https://orcid.org/0000-0002-1553-1432)
- Qinghua Zhang
- Haijun Cao
Institutions
- Beijing Institute of Technology (CN)
- Chinese Academy of Sciences (CN)
- Songshan Lake Materials Laboratory (CN)
- FZU ‒ Institute of Physics of the Academy of Sciences of the Czech Republic (CZ)
- Advanced Research Institute (US)
- Institute of Physics (CN)
- National Laboratory for Superconductivity (CN)
- University of Chinese Academy of Sciences (CN)
Publication Details
- Journal
- Nano Letters
- Published
- 2025-03-26
- DOI
- https://doi.org/10.1021/acs.nanolett.5c00536
- Citations
- 2
- Primary Topic
- Spectroscopy and Quantum Chemical Studies
- Type
- article
- Field-Weighted Citation Impact
- 2.49
Funders
- National Natural Science Foundation of China
- National Key Research and Development Program of China