標題: | Plasmonic Enhancement and Manipulation of Optical Nonlinearity in Monolayer Tungsten Disulfide |
作者: | Shi, Jinwei Liang, Wei-Yun Raja, Soniya S. Sang, Yungang Zhang, Xin-Quan Chen, Chun-An Wang, Yanrong Yang, Xinyue Lee, Yi-Hsien Ahn, Hyeyoung Gwo, Shangjr 光電工程學系 Department of Photonics |
關鍵字: | 2D materials;nonlinear optics;plasmonic metasurfaces;second-harmonic generation;transition metal dichalcogenides |
公開日期: | 1-Oct-2018 |
摘要: | Monolayer transition metal dichalcogenides (TMDCs) have large second-order optical nonlinearity owing to broken inversion symmetry in two-dimensional (2D) crystals. However, despite the strong light-matter coupling in monolayer TMDCs, their nonlinear responses are ultimately limited by subnanometer thickness. Here, a dramatic enhancement of the second-harmonic generation (SHG) is achieved from monolayer tungsten disulfide (WS2) incorporated onto a 2D silver (Ag) nanogroove grating with subwavelength pitch. By tuning surface plasmon mode and second-harmonic frequency in resonance with the C exciton in WS2, a large SHG enhancement factor (approximate to 400) and a large conversion efficiency (approximate to 2.0 x 10(-5)) can be obtained. Furthermore, the azimuthal angle dependence of polarized SHG from monolayer WS2 can be manipulated by the nanogroove plasmonic mode. Based on this property, a polarization-modulated optical encoding technique is demonstrated. The results suggest that 2D TMDC-plasmonic hybrid metasurface structures can provide an ideal integration platform for on-chip nonlinear photonics and plasmonics. |
URI: | http://dx.doi.org/10.1002/lpor.201800188 http://hdl.handle.net/11536/148273 |
ISSN: | 1863-8880 |
DOI: | 10.1002/lpor.201800188 |
期刊: | LASER & PHOTONICS REVIEWS |
Volume: | 12 |
Appears in Collections: | Articles |