Boosting classical and quantum nonlinear processes in ultrathin van der Waals materials
Understanding and controlling nonlinear processes is crucial for engineering light-matter interaction and generating non-classical light. A significant challenge in ultra-thin nonlinear materials is the marked diminution of the nonlinear conversion efficiency due to the reduced light-matter interaction length and, in many cases, the centrosymmetric crystalline structures. Here we relax these limitations and report a giant boost of classical and quantum nonlinear processes in ultrathin van der Waals materials. Specifically, with a metal-nonlinear material heterostructure we enhance classical second-harmonic generation in h-BN flakes by two orders of magnitude. Moreover, we have engineered a metal-SiO<sub>2</sub>-nonlinear material heterostructure resulting in a remarkable two orders of magnitude augmentation of the quantum spontaneous parametric down-conversion (SPDC) in NbOCl<sub>2</sub> flakes. Notably, we demonstrate SPDC in a 16 nm-thick NbOCl<sub>2</sub> flake integrated into the proposed structure. These findings simplify on-chip quantum state engineering and accelerate the use of van der Waals materials in nonlinear optoelectronics.
Authors
- Alexander Ling (ORCID: https://orcid.org/0000-0001-6194-9875)
- Ruihuan Duan (ORCID: https://orcid.org/0000-0003-4999-9735)
- Qinghai Tan (ORCID: https://orcid.org/0000-0003-4808-4795)
- Jesús Zúñiga-Pérez (ORCID: https://orcid.org/0000-0002-7154-641X)
- Chusheng Zhang
- Ruihua He (ORCID: https://orcid.org/0000-0003-3235-1991)
- Xiaodan Lyu
- Liheng An (ORCID: https://orcid.org/0000-0002-3345-0847)
- Hongbing Cai (ORCID: https://orcid.org/0000-0003-3186-1041)
- Yansong Miao (ORCID: https://orcid.org/0000-0003-1551-7873)
- Weibo Gao (ORCID: https://orcid.org/0000-0003-3971-621X)
- Zheng Liu (ORCID: https://orcid.org/0000-0002-8825-7198)
- Shuin Jian Wu (ORCID: https://orcid.org/0009-0002-9065-8721)
- Leevi Kallioniemi (ORCID: https://orcid.org/0009-0001-8621-6595)
Institutions
- Centre for Quantum Technologies (SG)
- University of Science and Technology of China (CN)
- Centre National de la Recherche Scientifique (FR)
- National University of Singapore (SG)
- Nanyang Technological University (SG)
- Sorbonne Université (FR)
- UMI MajuLab (SG)
Publication Details
- Journal
- Nature Communications
- Published
- 2025-05-29
- DOI
- https://doi.org/10.1038/s41467-025-58449-3
- Citations
- 6
- Primary Topic
- Advanced Fiber Laser Technologies
- Type
- article
- Field-Weighted Citation Impact
- 7.48
Funders
- National Research Foundation
- National Research Foundation Singapore