Premium
Plasmonic Enhancement and Manipulation of Optical Nonlinearity in Monolayer Tungsten Disulfide
Author(s) -
Shi Jinwei,
Liang WeiYun,
Raja Soniya S.,
Sang Yungang,
Zhang XinQuan,
Chen ChunAn,
Wang Yanrong,
Yang Xinyue,
Lee YiHsien,
Ahn Hyeyoung,
Gwo Shangjr
Publication year - 2018
Publication title -
laser and photonics reviews
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 3.778
H-Index - 116
eISSN - 1863-8899
pISSN - 1863-8880
DOI - 10.1002/lpor.201800188
Subject(s) - monolayer , plasmon , materials science , second harmonic generation , tungsten disulfide , optoelectronics , surface plasmon resonance , photonics , nanophotonics , point reflection , grating , nonlinear optics , tungsten , optics , nanotechnology , condensed matter physics , physics , nanoparticle , laser , metallurgy
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 (WS 2 ) 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 WS 2 , a large SHG enhancement factor (≈400) and a large conversion efficiency (≈2.0 × 10 –5 ) can be obtained. Furthermore, the azimuthal angle dependence of polarized SHG from monolayer WS 2 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.