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
This paper summarizes our research work on optoelectronic devices with nanostructures. It was indi- cated that by manipulating so called ＂general energybands＂ of fundamental particles or quasi-particles, such as pho...This paper summarizes our research work on optoelectronic devices with nanostructures. It was indi- cated that by manipulating so called ＂general energybands＂ of fundamental particles or quasi-particles, such as photon, phonon, and surface plasmon polariton （SPP）, novel optoelectronic characteristics can be obtained, which results in a series of new functional devices. A silicon based optical switch with an extremely broadband of 24 nm and an ultra-compact （8 μm -17.6μm） footprint was demonstrated with a photonic crystal slow light waveguides. By proposing a nanobeam based hereto optomechanical crystal, a high phonon frequency of 5.66 GHz was realized experimentally. Also, we observed and verified a novel effect of two-surface-plasmon-absorption （TSPA）, and realized diffraction-limit-overcoming photolithography with resolution of-1/11 of the exposure wavelength.展开更多
Surface plasmon polariton （SPP） is an attractive candidate to improve internal quantum efficiency （QE） of spontaneous emission （SE） from nano-structured silicon （Si） including nano-porous silicon （NP-Si） and...Surface plasmon polariton （SPP） is an attractive candidate to improve internal quantum efficiency （QE） of spontaneous emission （SE） from nano-structured silicon （Si） including nano-porous silicon （NP-Si） and silicon nanocrystal （Si-NC）. Since the SPP resonant frequency of common metals, e.g., gold （Au）, silver （Ag）, copper （Cu）, and aluminum （A1）, is too high, the SPP resonance has to be engineered to match the luminescence from nano- structured Si. For this purpose, we have proposed and demonstrated three approaches including metal-rich Au（1-a）-SiO2（a） cermet SPP waveguide （WG）, com- pound layer structure WG and metallic grating. In this paper, those approaches are reviewed and discussed. According to the calculated results, such three methods could effectively enhance SE rate from NP-Si or Si-NCs and show potential in developing high efficiency Si based light sources with electric pump.展开更多
Knowledge of surface plasmon polariton （SPP） modes in one-dimensional （1D） metallic nanostructures is essential for the development of subwavelength optical devices such as photonic circuits, integrated light sour...Knowledge of surface plasmon polariton （SPP） modes in one-dimensional （1D） metallic nanostructures is essential for the development of subwavelength optical devices such as photonic circuits, integrated light sources, and photo- detectors. Despite many efforts to characterize the propagation parameters of these subwavelength 1D plasmonic waveguides, such as Ag nanowires, large discrepancies exist among available reports owing to their sensitivity to the relative weights of co-existing SPP modes and the lack of a method of decoupling these modes and analyzing them separately. In this work, we develop an interference method to distinguish different SPP modes that are simultaneously excited in a Ag nanowire waveguide and measure their propagation parameters separately. By extracting information from the propagation-distance- dependent intensity oscillations of the scattered light from the nanowire tip, the effective refractive indices, propagation lengths, and relative mode weights of co-existing SPP modes supported by the nanowire are derived from a mode interference model. These parameters depend strongly on the nanowire diameter and excitation wavelength. In particular, we demonstrate the possibility of selective excitation of different SPP modes by varying the nanowire diameter. This new mode analysis technique provides unique insights into the develop- ment and optimization of SPP-based applications.展开更多
Plasmonics squeezes light into dimensions far beyond the diffraction limit by coupling the light with the surface collective oscillation of free electrons at the interface of a metal and a dielectric. Plasmonics, refe...Plasmonics squeezes light into dimensions far beyond the diffraction limit by coupling the light with the surface collective oscillation of free electrons at the interface of a metal and a dielectric. Plasmonics, referred to as a promising candidate for high-speed and high- density integrated circuits, bridges microscale photonics and nanoscale electronics and offers similar speed of photonic devices and similar dimension of electronic devices. Various types of passive and active surface plasmon polariton （SPP） enabled devices with enhanced deep-subwavelength mode confinement have attracted increasing interest including waveguides, lasers and biosensors. Despite the trade-off between the unavoidable metal absorption loss and extreme light concentration, the ever-increasing research efforts have been devoted to seeking low-loss plasmon-assisted nanophotonic devices with deep-subwavelength mode confinement, which might find potential applications in high-density nanophotonic integration and efficient nonlinear signal processing. In addition, other plasmon-assisted nanophotonic devices might also promote grooming functionalities and applica- tions benefiting from plasmonics. In this review article, we give a brief overview of our recent progress in plasmon-assisted nanophotonic devices and their wide applications, including long-range hybrid plasmonic slot （LRHPS） waveguide, ultra-compact plasmonic microresonator with efficient thermo-optic tuning, high quality （Q） factor and small mode volume, compact active hybrid plasmonic ring resonator for deep-subwave- length lasing applications, fabricated hybrid plasmonic waveguides for terabit-scale photonic interconnection, and metamaterials-based broadband and selective generation of orbital angular momentum （OAM） carrying vector beams. It is believed that plasmonics opens possible new ways to facilitate next chip-scale key devices and frontier technologies.展开更多
This study uses a dipole embedded in A1203 layer to excite a symmetric surface plasmon polariton （SPP） mode in Au/A1203/Au waveguide to investigate its profile properties by using finite-difference time-domain （FDT...This study uses a dipole embedded in A1203 layer to excite a symmetric surface plasmon polariton （SPP） mode in Au/A1203/Au waveguide to investigate its profile properties by using finite-difference time-domain （FDTD） method. The excited dipole decay radiatively direct near-field coupling to SPP mode owing to thin A1203 layer of 100 nm. The effects of electric and magnetic field intensity profiles and decay length have been considered and characterized. It is found that dipole location is an important factor to influence the horizontal and vertical profile properties of symmetric SPP mode in Au/A1203/Au waveguide. The amplitudes of electric and magnetic field intensity and the wavelengths of metal-insulatormetal （MIM） SPP resonance mode can be tuned by varying dipole location. The horizontal and vertical decay lengths are 19 and 24 nm, respectively. It is expected that the Au/A1203/Au waveguide structure is very useful for the practical applications of designing a SPP source.展开更多
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This work was supported by the National Basic Research Program of China （No. 2013CB328704 and 2013CBA01704）, the National Natural Science Foundation of China （Grant No. 61307068）.
文摘This paper summarizes our research work on optoelectronic devices with nanostructures. It was indi- cated that by manipulating so called ＂general energybands＂ of fundamental particles or quasi-particles, such as photon, phonon, and surface plasmon polariton （SPP）, novel optoelectronic characteristics can be obtained, which results in a series of new functional devices. A silicon based optical switch with an extremely broadband of 24 nm and an ultra-compact （8 μm -17.6μm） footprint was demonstrated with a photonic crystal slow light waveguides. By proposing a nanobeam based hereto optomechanical crystal, a high phonon frequency of 5.66 GHz was realized experimentally. Also, we observed and verified a novel effect of two-surface-plasmon-absorption （TSPA）, and realized diffraction-limit-overcoming photolithography with resolution of-1/11 of the exposure wavelength.
基金Acknowledgements This work was supported by the National Basic Research Program of China （No. 2011CBA00600 and 2007CB307004） and the National Natural Science Foundation of China （Grant Nos. 60877023, 61036010, 61036011, and 61107050）. The authors would like to thank Xuan Tang, Weiwei Ke, Wei Zhang and Jiangde Peng for their valuable discussions and helpful comments.
文摘Surface plasmon polariton （SPP） is an attractive candidate to improve internal quantum efficiency （QE） of spontaneous emission （SE） from nano-structured silicon （Si） including nano-porous silicon （NP-Si） and silicon nanocrystal （Si-NC）. Since the SPP resonant frequency of common metals, e.g., gold （Au）, silver （Ag）, copper （Cu）, and aluminum （A1）, is too high, the SPP resonance has to be engineered to match the luminescence from nano- structured Si. For this purpose, we have proposed and demonstrated three approaches including metal-rich Au（1-a）-SiO2（a） cermet SPP waveguide （WG）, com- pound layer structure WG and metallic grating. In this paper, those approaches are reviewed and discussed. According to the calculated results, such three methods could effectively enhance SE rate from NP-Si or Si-NCs and show potential in developing high efficiency Si based light sources with electric pump.
文摘Knowledge of surface plasmon polariton （SPP） modes in one-dimensional （1D） metallic nanostructures is essential for the development of subwavelength optical devices such as photonic circuits, integrated light sources, and photo- detectors. Despite many efforts to characterize the propagation parameters of these subwavelength 1D plasmonic waveguides, such as Ag nanowires, large discrepancies exist among available reports owing to their sensitivity to the relative weights of co-existing SPP modes and the lack of a method of decoupling these modes and analyzing them separately. In this work, we develop an interference method to distinguish different SPP modes that are simultaneously excited in a Ag nanowire waveguide and measure their propagation parameters separately. By extracting information from the propagation-distance- dependent intensity oscillations of the scattered light from the nanowire tip, the effective refractive indices, propagation lengths, and relative mode weights of co-existing SPP modes supported by the nanowire are derived from a mode interference model. These parameters depend strongly on the nanowire diameter and excitation wavelength. In particular, we demonstrate the possibility of selective excitation of different SPP modes by varying the nanowire diameter. This new mode analysis technique provides unique insights into the develop- ment and optimization of SPP-based applications.
基金Acknowledgements This work was supported by the National Natural Science Foundation of China （NSFC） （Grants Nos. 61222502, 61077051, 11274131 and L1222026）, the National Basic Research Program of China （973 Program） （No. 2014CB340004）, the Program for New Century Excellent Talents in University （NCET-11-0182）, the Wuhan Science and Technology Plan Project （No. 2014070404010201）, the Fundamental Research Funds of the Central Universities （HUST） （Nos. 2012YQ008 and 2013ZZGH003）, and the seed project of Wuhan National Laboratory for Optoelectronics （WNLO）.
文摘Plasmonics squeezes light into dimensions far beyond the diffraction limit by coupling the light with the surface collective oscillation of free electrons at the interface of a metal and a dielectric. Plasmonics, referred to as a promising candidate for high-speed and high- density integrated circuits, bridges microscale photonics and nanoscale electronics and offers similar speed of photonic devices and similar dimension of electronic devices. Various types of passive and active surface plasmon polariton （SPP） enabled devices with enhanced deep-subwavelength mode confinement have attracted increasing interest including waveguides, lasers and biosensors. Despite the trade-off between the unavoidable metal absorption loss and extreme light concentration, the ever-increasing research efforts have been devoted to seeking low-loss plasmon-assisted nanophotonic devices with deep-subwavelength mode confinement, which might find potential applications in high-density nanophotonic integration and efficient nonlinear signal processing. In addition, other plasmon-assisted nanophotonic devices might also promote grooming functionalities and applica- tions benefiting from plasmonics. In this review article, we give a brief overview of our recent progress in plasmon-assisted nanophotonic devices and their wide applications, including long-range hybrid plasmonic slot （LRHPS） waveguide, ultra-compact plasmonic microresonator with efficient thermo-optic tuning, high quality （Q） factor and small mode volume, compact active hybrid plasmonic ring resonator for deep-subwave- length lasing applications, fabricated hybrid plasmonic waveguides for terabit-scale photonic interconnection, and metamaterials-based broadband and selective generation of orbital angular momentum （OAM） carrying vector beams. It is believed that plasmonics opens possible new ways to facilitate next chip-scale key devices and frontier technologies.
基金Acknowledgements This work was supported by the National Natural Science Foundation of China （Grant Nos. 60907024 and 61036011）, the New Teachers＇ Fund for the Doctoral Program of Higher Education （No. 20100001120024）, Scientific Research Foundation for the Returned Overseas Chinese Scholars, State Education Ministry.
文摘This study uses a dipole embedded in A1203 layer to excite a symmetric surface plasmon polariton （SPP） mode in Au/A1203/Au waveguide to investigate its profile properties by using finite-difference time-domain （FDTD） method. The excited dipole decay radiatively direct near-field coupling to SPP mode owing to thin A1203 layer of 100 nm. The effects of electric and magnetic field intensity profiles and decay length have been considered and characterized. It is found that dipole location is an important factor to influence the horizontal and vertical profile properties of symmetric SPP mode in Au/A1203/Au waveguide. The amplitudes of electric and magnetic field intensity and the wavelengths of metal-insulatormetal （MIM） SPP resonance mode can be tuned by varying dipole location. The horizontal and vertical decay lengths are 19 and 24 nm, respectively. It is expected that the Au/A1203/Au waveguide structure is very useful for the practical applications of designing a SPP source.
