A phoxonic crystal waveguide with the glide symmetry is designed,in which both electromagnetic and elastic waves can propagate along the glide plane at the same time.Due to the glide symmetry,the bands of the phoxonic...A phoxonic crystal waveguide with the glide symmetry is designed,in which both electromagnetic and elastic waves can propagate along the glide plane at the same time.Due to the glide symmetry,the bands of the phoxonic crystal super-cell degenerate in pairs at the boundary of the Brillouin zone.This is the so-called band-sticking effect and it causes the appearance of gapless guided-modes.By adjusting the magnitude of the glide dislocation the edge bandgaps,the bandgap of the guided-modes at the boundary of the Brillouin zone,can be further adjusted.The photonic and phononic guided-modes can then possess only one mode for a certain frequency with relatively low group velocities,achieving single-mode guided-bands with relatively flat dispersion relationship.In addition,there exists acousto-optic interaction in the cavity constructed by the glide plane.The proposed waveguide has potential applications in the design of novel optomechanical devices.展开更多
We propose an ultracompact triplexer based on a shift of the cutoff frequency of the fundamental mode in a planar photonie crystal waveguide （PCW） with a triangular lattice of air holes. The shift is realized by mod...We propose an ultracompact triplexer based on a shift of the cutoff frequency of the fundamental mode in a planar photonie crystal waveguide （PCW） with a triangular lattice of air holes. The shift is realized by modifying the radii of the border holes adjacent to the PCW core. Some defect holes are introduced to control the beam propagation. The numerical results obtained by the finite-difference time-domain method show that the presented triplexer can separate three specific wavelengths, i.e. 1310, 1490 and 1550nm with the extinction ratios higher than -18 dB. The designed device with a size as compact as 12 μm × 6.5μ m is feasible for the practical application, and can be utilized in the system of fiber to the home.展开更多
Based on the coupling between photonic crystals(PCs) waveguide and micro-cavity,a new method to design wavelength division multiplexing(WDM) is proposed.By changing the position of border dielectric rods of micro-cavi...Based on the coupling between photonic crystals(PCs) waveguide and micro-cavity,a new method to design wavelength division multiplexing(WDM) is proposed.By changing the position of border dielectric rods of micro-cavity and adopting the output waveguide with a 60o bend,the property of micro-cavity is optimized.The new WDM is designed based on the model.And by modulating the border dielectric rods,different wavelengths can be coupled into the micro-cavity,and then are output from the load waveguide selectively.Only by adding a reflective layer in the bus waveguide,the transmission efficiency of output wavelengths is greatly improved.展开更多
基金Project supported by the National Natural Science Foundation of China(Grant No.12064025)the Natural Science Foundation of Jiangxi Province,China(Grant No.20212ACB202006)+1 种基金the Major Discipline Academic and Technical Leaders Training Program of Jiangxi Province,China(Grant No.20204BCJ22012)the Open Project of the Key Laboratory of Radar Imaging and Microwave Photonic Technology of the Education Ministry of China.
文摘A phoxonic crystal waveguide with the glide symmetry is designed,in which both electromagnetic and elastic waves can propagate along the glide plane at the same time.Due to the glide symmetry,the bands of the phoxonic crystal super-cell degenerate in pairs at the boundary of the Brillouin zone.This is the so-called band-sticking effect and it causes the appearance of gapless guided-modes.By adjusting the magnitude of the glide dislocation the edge bandgaps,the bandgap of the guided-modes at the boundary of the Brillouin zone,can be further adjusted.The photonic and phononic guided-modes can then possess only one mode for a certain frequency with relatively low group velocities,achieving single-mode guided-bands with relatively flat dispersion relationship.In addition,there exists acousto-optic interaction in the cavity constructed by the glide plane.The proposed waveguide has potential applications in the design of novel optomechanical devices.
基金Supported by the National Natural Science Foundation of China under Grant No 10664002, the Natural Science Foundation of Jiangxi Province under Grant Nos 0612043, 2007CQW2057 and 2007GZW2457, and the Open Funds of the State Key Laboratory on Integrated Optoelectronics of Institute of Semiconductors （IOSKL-KF200901）.
文摘We propose an ultracompact triplexer based on a shift of the cutoff frequency of the fundamental mode in a planar photonie crystal waveguide （PCW） with a triangular lattice of air holes. The shift is realized by modifying the radii of the border holes adjacent to the PCW core. Some defect holes are introduced to control the beam propagation. The numerical results obtained by the finite-difference time-domain method show that the presented triplexer can separate three specific wavelengths, i.e. 1310, 1490 and 1550nm with the extinction ratios higher than -18 dB. The designed device with a size as compact as 12 μm × 6.5μ m is feasible for the practical application, and can be utilized in the system of fiber to the home.
基金supported by the Natural Science Foundation of Jiangxi Province of China (No. 2008GZW0007)
文摘Based on the coupling between photonic crystals(PCs) waveguide and micro-cavity,a new method to design wavelength division multiplexing(WDM) is proposed.By changing the position of border dielectric rods of micro-cavity and adopting the output waveguide with a 60o bend,the property of micro-cavity is optimized.The new WDM is designed based on the model.And by modulating the border dielectric rods,different wavelengths can be coupled into the micro-cavity,and then are output from the load waveguide selectively.Only by adding a reflective layer in the bus waveguide,the transmission efficiency of output wavelengths is greatly improved.
