We investigate the electrically controlled light propagation in the metal–dielectric–metal plasmonic waveguide with a sandwiched graphene monolayer. The theoretical and simulation results show that the propagation l...We investigate the electrically controlled light propagation in the metal–dielectric–metal plasmonic waveguide with a sandwiched graphene monolayer. The theoretical and simulation results show that the propagation loss exhibits an obvious peak when the permittivity of graphene approaches an epsilon-near-zero point when adjusting the gate voltage on graphene. The analog of electromagnetically induced transparency(EIT) can be generated by introducing side-coupled stubs into the waveguide. Based on the EIT-like effect, the hybrid plasmonic waveguide with a length of only 1.5 μm can work as a modulator with an extinction ratio of ～15.8 d B, which is 2.3times larger than the case without the stubs. The active modulation of surface plasmon polariton propagation can be further improved by tuning the carrier mobility of graphene. The graphene-supported plasmonic waveguide system could find applications for the nanoscale manipulation of light and chip-integrated modulation.展开更多
Based on the transverse second-harmonic generation(TSHG) effect, we demonstrate a method for in-situ modal inspection of nonlinear micro/nanowaveguides.Pumping lights are equally split and coupled into two ends of a s...Based on the transverse second-harmonic generation(TSHG) effect, we demonstrate a method for in-situ modal inspection of nonlinear micro/nanowaveguides.Pumping lights are equally split and coupled into two ends of a single Cd S nanobelt(NB).As pumping light counter-propagates along the NB, transverse second-harmonic(TSH) interference patterns are observed.The influence of multimode interaction on the TSHG effect is discussed in detail.Using fast Fourier transform,TSH interference patterns are analyzed, indicating the existence of at least four modes inside the NB.Experimental beat lengths are found to be in agreement with calculated results.展开更多
We design and fabricate an unbalanced Mach–Zehnder interferometer(MZI)via electron beam lithography and inductively coupled plasma etching on lithium niobate thin film.The single unbalanced MZI exhibits a maximum ext...We design and fabricate an unbalanced Mach–Zehnder interferometer(MZI)via electron beam lithography and inductively coupled plasma etching on lithium niobate thin film.The single unbalanced MZI exhibits a maximum extinction ratio of 32.4 dB and a low extra loss of 1.14 dB at the telecommunication band.Furthermore,tunability of the unbalanced MZI by harnessing the thermo-optic and electro-optic effect is investigated,achieving a linear tuning efficiency of 42.8 pm/℃ and 55.2 pm/V,respectively.The demonstrated structure has applications for sensing and filtering in photonic integrated circuits.展开更多
基金National Natural Science Foundation of China(NSFC)(11634010,61377035,61522507,61575162)Fundamental Research Funds for the Central Universities(3102016OQD031,G2016KY0303)
文摘We investigate the electrically controlled light propagation in the metal–dielectric–metal plasmonic waveguide with a sandwiched graphene monolayer. The theoretical and simulation results show that the propagation loss exhibits an obvious peak when the permittivity of graphene approaches an epsilon-near-zero point when adjusting the gate voltage on graphene. The analog of electromagnetically induced transparency(EIT) can be generated by introducing side-coupled stubs into the waveguide. Based on the EIT-like effect, the hybrid plasmonic waveguide with a length of only 1.5 μm can work as a modulator with an extinction ratio of ～15.8 d B, which is 2.3times larger than the case without the stubs. The active modulation of surface plasmon polariton propagation can be further improved by tuning the carrier mobility of graphene. The graphene-supported plasmonic waveguide system could find applications for the nanoscale manipulation of light and chip-integrated modulation.
基金supported by the Science and Technology Innovation Program of Shanxi Province (No.19004454)。
文摘Based on the transverse second-harmonic generation(TSHG) effect, we demonstrate a method for in-situ modal inspection of nonlinear micro/nanowaveguides.Pumping lights are equally split and coupled into two ends of a single Cd S nanobelt(NB).As pumping light counter-propagates along the NB, transverse second-harmonic(TSH) interference patterns are observed.The influence of multimode interaction on the TSHG effect is discussed in detail.Using fast Fourier transform,TSH interference patterns are analyzed, indicating the existence of at least four modes inside the NB.Experimental beat lengths are found to be in agreement with calculated results.
基金supported by the National Natural Science Foundation of China(Nos.12074252,62022058,62005159,and 11734011)National Key Research and Development Program of China(Nos.2017YFA0303701 and 2018YFA0306301)+2 种基金Shanghai Municipal Science and Technology Major Project(No.2019SHZDZX01-ZX06)Shanghai Rising-Star Program(No.20QA1405400)Shanghai Jiao Tong University(No.21X010200828)。
文摘We design and fabricate an unbalanced Mach–Zehnder interferometer(MZI)via electron beam lithography and inductively coupled plasma etching on lithium niobate thin film.The single unbalanced MZI exhibits a maximum extinction ratio of 32.4 dB and a low extra loss of 1.14 dB at the telecommunication band.Furthermore,tunability of the unbalanced MZI by harnessing the thermo-optic and electro-optic effect is investigated,achieving a linear tuning efficiency of 42.8 pm/℃ and 55.2 pm/V,respectively.The demonstrated structure has applications for sensing and filtering in photonic integrated circuits.
