Resonance cavity is a basic element in optics,which has wide applications in optical devices.Coupled cavities(CCs)designed in metal-insulator-metal(MIM)bus waveguide are investigated through the finite difference time...Resonance cavity is a basic element in optics,which has wide applications in optical devices.Coupled cavities(CCs)designed in metal-insulator-metal(MIM)bus waveguide are investigated through the finite difference time domain method and coupled-mode theory.In the CCs,the resonant modes of the surface plasmon polaritons(SPPs)split with the thickness decreasing of the middle baffle.Through the coupled-mode theory analysis,it is found that the phase differences introduced in opposite and positive couplings between two cavities lead to mode splitting.The resonant wavelength of positive coupling mode can be tuned in a large range(about 644 nm)through adjusting the coupling strength,which is quite different from the classical adjustment of the optical path in a single cavity.Based on the resonances of the CCs in the MIM waveguide,more compact devices can be designed to manipulate SPPs propagation.A device is designed to realize flexible multiple-wavelength SPPs routing.The coupling in CC structures can be applied to the design of easy-integrated laser cavities,filters,multiple-wavelength management devices in SPPs circuits,nanosensors,etc.展开更多
Low profile and light weight are very important for practical applications of a spoof surface plasmon polariton(SSPP)coupler, especially at low frequencies. In this paper, we propose and design an ultra-thin, light-...Low profile and light weight are very important for practical applications of a spoof surface plasmon polariton(SSPP)coupler, especially at low frequencies. In this paper, we propose and design an ultra-thin, light-weight SSPP coupler based on broadside coupled split ring resonators(BC-SRRs). The size of BC-SRR can be far less than λ/100 and can extremely well control the reflective phases within a subwavelength thickness. Due to the broadside capacitive coupling, the electrical size of BC-SRR is dramatically reduced to guarantee the ultra-thin thickness of the SSPP coupler. The weight of the SSPP coupler is reduced by a low occupation ratio of BC-SRR in the unit cell volume. As an example, a C-band SSPP coupler composed of phase gradient BC-SRRs is designed, fabricated, and measured. Due to the ultra-small size and low occupation ratio of BC-SRRs, the thickness of the coupler is λ/12 and the surface density is only 0.98 kg/m^2. Both simulation and experiment results verify that the coupler can achieve high-efficiency SPP coupling at 5.27 GHz under normal incidence.展开更多
To reveal and utilize the interaction between Tamm plasmon polaritons(TPPs)and two-dimensional materials are promising for exploiting next-generation optoelectronic devices.Herein,the coupling mechanism between metal ...To reveal and utilize the interaction between Tamm plasmon polaritons(TPPs)and two-dimensional materials are promising for exploiting next-generation optoelectronic devices.Herein,the coupling mechanism between metal TPPs and monolayer WS_(2) along with its differences from that between metal TPPs and graphene was studied in detail by using the transfer matrix method.The experimental results show that it is difficult to excite TPPs at the boundary between monolayer WS_(2) and dielectric Bragg reflector(DBR)such that the strong coupling mainly stems from the interaction between metal TPPs and exciton in monolayer WS_(2).However,the coupling in graphene/DBR/metal hybrid structure derives from the interaction between two different TPP resonance modes.Thus,evolutions of Rabi splitting with various structural parameters including spacer thickness,incident angle and DBR period greatly differ from those observed in graphene/DBR/metal hybrid structure.In addition,the discrepancies induced via metal Ag and Au films as well as the possible influence mechanism were also discussed.展开更多
The coupling interaction between an individual optical emitter and the propagating surface plasmon polaritons in a graphene microribbon (GMR) waveguide is investigated by numerical calculations, where the emitter is...The coupling interaction between an individual optical emitter and the propagating surface plasmon polaritons in a graphene microribbon (GMR) waveguide is investigated by numerical calculations, where the emitter is situated above the GMR or in the same plane of the GMR, The results reveal a multimode coupling mechanism for the strong interaction between the emitter and the propagating plasmonic waves in graphene. When the emitter is situated in the same plane of the GMR, the decay rate from the emitter to the surface plasmon polaritons increases more than 10 times compared with that in the case with the emitter above the GMR.展开更多
Narrow bandpass filters(NBPFs)play important roles in optics,such as quantum communication,spectrometer,and wavelength division multiplexing.However,the stopband and restraint ability of traditional NBPFs is limited.I...Narrow bandpass filters(NBPFs)play important roles in optics,such as quantum communication,spectrometer,and wavelength division multiplexing.However,the stopband and restraint ability of traditional NBPFs is limited.In this article,a coupled Tamm plasmon polaritons(TPPs)induced transmission theory has been proposed to design high-efficiency NBPFs with ultra-wide deep stopbands.An NBPF at 1.55 μm has been experimentally demonstrated with full width at half maximum(FWHM)of 10 nm and stopband ranging from 0.2 to 25 μm which is 62 times wider than that of traditional ones.Furthermore,the restraint depth of the stopband reaches 0.03%,which is only 1/20 of a traditional filter with the same FWHM.Its advantage in restraining ambient light over traditional ones has also been demonstrated with an InGaAs infrared detector.It provides a very powerful way to capture specific narrowband optical signals from ultra-wide strong ambient light,especially useful for daytime quantum communications.展开更多
As a basic optical device, the optical directional coupler (ODC) is basically used as optical splitters, optic switches and so on. A novel ODC employing surface plas- mon polaritons (SPPs) is proposed for high integra...As a basic optical device, the optical directional coupler (ODC) is basically used as optical splitters, optic switches and so on. A novel ODC employing surface plas- mon polaritons (SPPs) is proposed for high integration. The finite difference time domain (FDTD) method is adopted to simulate and analyze its properties. Results show that the ODC proposed here follows the general regulations of a conventional dielectric ODC, but its transverse size is of nanoscale, which improves the optical integration greatly. For 1550 nm and 1310 nm input wavelengths, when the coupling region length (L) equals half of its coupling length, the Excess Loss is respectively 0.57 dB and 0.56 dB, which is practical in applications. So the research on the present ODC is of some practical importance.展开更多
We propose a design for efficient end-fire coupling of surface plasmon polaritons in a metal-insulator-metal(MIM) waveguide with an optical fiber as part of a simple photoplastic connector. The design was analyzed and...We propose a design for efficient end-fire coupling of surface plasmon polaritons in a metal-insulator-metal(MIM) waveguide with an optical fiber as part of a simple photoplastic connector. The design was analyzed and optimized using the three-dimensional finite-difference time-domain method. The calculated excitation efficiency coefficient of the waveguide is 83.7%(-0.77 dB) at a wavelength of 405 nm. This design enables simple connection of an optical fiber to a MIM waveguide and highly efficient local excitation of the waveguide.Moreover, the length of the metallic elements of the waveguide, and thus the dissipative losses, can be reduced.The proposed design may be useful in plasmonic-type waveguide applications such as near-field investigation of live cells and other objects with super-resolution.展开更多
基金the National Natural Science Foundation of China(Grant No.11764006).
文摘Resonance cavity is a basic element in optics,which has wide applications in optical devices.Coupled cavities(CCs)designed in metal-insulator-metal(MIM)bus waveguide are investigated through the finite difference time domain method and coupled-mode theory.In the CCs,the resonant modes of the surface plasmon polaritons(SPPs)split with the thickness decreasing of the middle baffle.Through the coupled-mode theory analysis,it is found that the phase differences introduced in opposite and positive couplings between two cavities lead to mode splitting.The resonant wavelength of positive coupling mode can be tuned in a large range(about 644 nm)through adjusting the coupling strength,which is quite different from the classical adjustment of the optical path in a single cavity.Based on the resonances of the CCs in the MIM waveguide,more compact devices can be designed to manipulate SPPs propagation.A device is designed to realize flexible multiple-wavelength SPPs routing.The coupling in CC structures can be applied to the design of easy-integrated laser cavities,filters,multiple-wavelength management devices in SPPs circuits,nanosensors,etc.
基金Project supported by the National Natural Science Foundation of China(Grant Nos.61331005,61471388,and 61501503)
文摘Low profile and light weight are very important for practical applications of a spoof surface plasmon polariton(SSPP)coupler, especially at low frequencies. In this paper, we propose and design an ultra-thin, light-weight SSPP coupler based on broadside coupled split ring resonators(BC-SRRs). The size of BC-SRR can be far less than λ/100 and can extremely well control the reflective phases within a subwavelength thickness. Due to the broadside capacitive coupling, the electrical size of BC-SRR is dramatically reduced to guarantee the ultra-thin thickness of the SSPP coupler. The weight of the SSPP coupler is reduced by a low occupation ratio of BC-SRR in the unit cell volume. As an example, a C-band SSPP coupler composed of phase gradient BC-SRRs is designed, fabricated, and measured. Due to the ultra-small size and low occupation ratio of BC-SRRs, the thickness of the coupler is λ/12 and the surface density is only 0.98 kg/m^2. Both simulation and experiment results verify that the coupler can achieve high-efficiency SPP coupling at 5.27 GHz under normal incidence.
基金Funded by the National Natural Science Foundation of China(No.11804251)the Tianjin University of Commerce(Nos.TJCUJG202086 and 201910069101)。
文摘To reveal and utilize the interaction between Tamm plasmon polaritons(TPPs)and two-dimensional materials are promising for exploiting next-generation optoelectronic devices.Herein,the coupling mechanism between metal TPPs and monolayer WS_(2) along with its differences from that between metal TPPs and graphene was studied in detail by using the transfer matrix method.The experimental results show that it is difficult to excite TPPs at the boundary between monolayer WS_(2) and dielectric Bragg reflector(DBR)such that the strong coupling mainly stems from the interaction between metal TPPs and exciton in monolayer WS_(2).However,the coupling in graphene/DBR/metal hybrid structure derives from the interaction between two different TPP resonance modes.Thus,evolutions of Rabi splitting with various structural parameters including spacer thickness,incident angle and DBR period greatly differ from those observed in graphene/DBR/metal hybrid structure.In addition,the discrepancies induced via metal Ag and Au films as well as the possible influence mechanism were also discussed.
基金Project supported by the National Natural Science Foundation of China(Grant Nos.51172030,11274052,51102019,51172208,and 61274015)the National Basic Research Program of China(Grant No.2010CB923200)
文摘The coupling interaction between an individual optical emitter and the propagating surface plasmon polaritons in a graphene microribbon (GMR) waveguide is investigated by numerical calculations, where the emitter is situated above the GMR or in the same plane of the GMR, The results reveal a multimode coupling mechanism for the strong interaction between the emitter and the propagating plasmonic waves in graphene. When the emitter is situated in the same plane of the GMR, the decay rate from the emitter to the surface plasmon polaritons increases more than 10 times compared with that in the case with the emitter above the GMR.
基金This work was funded by the National Natural Science Foundation of China(NSFC)(No.11874376)Shanghai Science and Technology Foundations(Nos.19DZ2293400,19ZR1465900,and 21WZ2504800)+3 种基金Shanghai Municipal Science and Technology Major Project(No.2019SHZDZX01)the Chinese Academy of Sciences President’s International Fellowship Initiative(Nos.2020VTA0009,2020PT0020,and 2021PT0007)And thanks to the support of Soft Matter Nanofab(No.SMN180827)Analytical Instrumentation Center(No.#SPST-AIC10112914)(SPST,ShanghaiTech University).
文摘Narrow bandpass filters(NBPFs)play important roles in optics,such as quantum communication,spectrometer,and wavelength division multiplexing.However,the stopband and restraint ability of traditional NBPFs is limited.In this article,a coupled Tamm plasmon polaritons(TPPs)induced transmission theory has been proposed to design high-efficiency NBPFs with ultra-wide deep stopbands.An NBPF at 1.55 μm has been experimentally demonstrated with full width at half maximum(FWHM)of 10 nm and stopband ranging from 0.2 to 25 μm which is 62 times wider than that of traditional ones.Furthermore,the restraint depth of the stopband reaches 0.03%,which is only 1/20 of a traditional filter with the same FWHM.Its advantage in restraining ambient light over traditional ones has also been demonstrated with an InGaAs infrared detector.It provides a very powerful way to capture specific narrowband optical signals from ultra-wide strong ambient light,especially useful for daytime quantum communications.
基金the Project of Guangdong Natural Science Funds for the Research on Nano-integrated Waveguide Devices Based On Surface Plasmon Polariton (Grant No. 07117866)the Key Project of the Natural Science Foundation of Guangdong Province of China (Grant No. 05200534)
文摘As a basic optical device, the optical directional coupler (ODC) is basically used as optical splitters, optic switches and so on. A novel ODC employing surface plas- mon polaritons (SPPs) is proposed for high integration. The finite difference time domain (FDTD) method is adopted to simulate and analyze its properties. Results show that the ODC proposed here follows the general regulations of a conventional dielectric ODC, but its transverse size is of nanoscale, which improves the optical integration greatly. For 1550 nm and 1310 nm input wavelengths, when the coupling region length (L) equals half of its coupling length, the Excess Loss is respectively 0.57 dB and 0.56 dB, which is practical in applications. So the research on the present ODC is of some practical importance.
基金National Natural Science Foundation of China(NSFC)(61571399)“The Belt and Road”International Cooperation of Zhejiang Province,China(2015C04005)
文摘We propose a design for efficient end-fire coupling of surface plasmon polaritons in a metal-insulator-metal(MIM) waveguide with an optical fiber as part of a simple photoplastic connector. The design was analyzed and optimized using the three-dimensional finite-difference time-domain method. The calculated excitation efficiency coefficient of the waveguide is 83.7%(-0.77 dB) at a wavelength of 405 nm. This design enables simple connection of an optical fiber to a MIM waveguide and highly efficient local excitation of the waveguide.Moreover, the length of the metallic elements of the waveguide, and thus the dissipative losses, can be reduced.The proposed design may be useful in plasmonic-type waveguide applications such as near-field investigation of live cells and other objects with super-resolution.
基金Supported by the National Natural Science Foundation of China(61231005,11305030,612111076)The National High Technology Research and Development Program of China(863 Program)(2011AA010204)+1 种基金the National Basic Research Program of China(973 Program)(2014CB33980)Fundamental Research Funds for the Central Universities(ZYGX2015KYQD064)~~