This paper summarizes the recent progress in Terahertz(THz) waveguides. Many THz waveguides of various sorts have been presented and examined, including dielectric THz waveguides, metal THz waveguides, THz fiber and p...This paper summarizes the recent progress in Terahertz(THz) waveguides. Many THz waveguides of various sorts have been presented and examined, including dielectric THz waveguides, metal THz waveguides, THz fiber and photonic crystal THz waveguides. Their advantages and limitations are stated, and the perspective of research on Terahertz waveguides is discussed.展开更多
The light propagation characteristics through the annular coupled-resonator cavity waveguides are systematically analyzed by the finite-difference time-domain (FDTD) method. It is found that this kind of waveguide has...The light propagation characteristics through the annular coupled-resonator cavity waveguides are systematically analyzed by the finite-difference time-domain (FDTD) method. It is found that this kind of waveguide has more minbands owing to the increasing of the cavity’s size, compared with the traditional line-typed coupled-resonator waveguide. The group velocity of light propagation can be reduced for a further degree when the adjacent annular cavities are interlaced in the perpendicular direction, and a group velocity about 0.00067c (c is the light speed in vacuum) can be obtained.展开更多
We present a novel mechanism,which is formed by periodically changing the radii of dielectric rods in the middle row of a photonic crystal, to control and stop light. Using the Bloch theory and coupled-mode theoryl th...We present a novel mechanism,which is formed by periodically changing the radii of dielectric rods in the middle row of a photonic crystal, to control and stop light. Using the Bloch theory and coupled-mode theoryl the dispersion characteristic of such a photonic crystal coupled cavity optical waveguide is obtained. We also theoretically demonstrate that the group velocity of a light pulse in this system can be modulated by dynamically changing the refractive index or radii of the selected dielectric rods, and the light stopping can be achieved.展开更多
We demonstrate a novel SOI-based photonic crystal（PC） double-heterostructure slot waveguide microcavity constructed by cascading three PC slot waveguides with different slot widths,and simulate the luminescence enha...We demonstrate a novel SOI-based photonic crystal（PC） double-heterostructure slot waveguide microcavity constructed by cascading three PC slot waveguides with different slot widths,and simulate the luminescence enhancement of sol-gel Er-doped SiO2 filled in the microcavity by finite-difference time-domain（FDTD） method.The calculated results indicate that a unique sharp resonant peak dominates in the spectrum at the expected telecommunication wavelength of 1.5509 mm,with very high normalized peak intensity of ~108.The electromagnetic field of the resonant mode exhibits the strongest in the microcavity,and decays rapidly to zero along both sides,which means that the resonant mode field is well confined in the microcavity.The simulation results fully verify the enhancement of luminescence by PC double-heterostructure slot waveguide microcavity theoretically,which is a promising way to realize the high-efficiency luminescence of Si-based materials.展开更多
In this paper,configuration parameters of the waveguide are altered independently or simultaneously to control the cutoff frequencies of the guided band.The independent control range of the upper and lower cutoff freq...In this paper,configuration parameters of the waveguide are altered independently or simultaneously to control the cutoff frequencies of the guided band.The independent control range of the upper and lower cutoff frequencies is 55.0% and 63.9% of the photonic band gap(PBG),respectively.The regulating range of the simultaneous tuning can be as large as 28.6% in terms of the PBG,or 240% in terms of the bandwidth.This tuning cutoff frequency method provides an efficient way to tailor the guided band and further tune the optical properties of PhCWs.展开更多
文摘This paper summarizes the recent progress in Terahertz(THz) waveguides. Many THz waveguides of various sorts have been presented and examined, including dielectric THz waveguides, metal THz waveguides, THz fiber and photonic crystal THz waveguides. Their advantages and limitations are stated, and the perspective of research on Terahertz waveguides is discussed.
基金supported by the National Natural Science Foundation of China (Nos.10904176 and 11004169)the NMOE Project of China (Nos.200911002 and 2010110009)
文摘The light propagation characteristics through the annular coupled-resonator cavity waveguides are systematically analyzed by the finite-difference time-domain (FDTD) method. It is found that this kind of waveguide has more minbands owing to the increasing of the cavity’s size, compared with the traditional line-typed coupled-resonator waveguide. The group velocity of light propagation can be reduced for a further degree when the adjacent annular cavities are interlaced in the perpendicular direction, and a group velocity about 0.00067c (c is the light speed in vacuum) can be obtained.
基金supported by the National Natural Science Foundation of China(No.10874128)
文摘We present a novel mechanism,which is formed by periodically changing the radii of dielectric rods in the middle row of a photonic crystal, to control and stop light. Using the Bloch theory and coupled-mode theoryl the dispersion characteristic of such a photonic crystal coupled cavity optical waveguide is obtained. We also theoretically demonstrate that the group velocity of a light pulse in this system can be modulated by dynamically changing the refractive index or radii of the selected dielectric rods, and the light stopping can be achieved.
基金supported by the National Key Basic Research Special Fund of China (No.2007CB613404)the National High Technology,Research and Development Program of China (No.2011AA010303)the National Natural Science Foundation of China (Nos.61090390,60837001,60977045,60877014 and 60776057)
文摘We demonstrate a novel SOI-based photonic crystal（PC） double-heterostructure slot waveguide microcavity constructed by cascading three PC slot waveguides with different slot widths,and simulate the luminescence enhancement of sol-gel Er-doped SiO2 filled in the microcavity by finite-difference time-domain（FDTD） method.The calculated results indicate that a unique sharp resonant peak dominates in the spectrum at the expected telecommunication wavelength of 1.5509 mm,with very high normalized peak intensity of ~108.The electromagnetic field of the resonant mode exhibits the strongest in the microcavity,and decays rapidly to zero along both sides,which means that the resonant mode field is well confined in the microcavity.The simulation results fully verify the enhancement of luminescence by PC double-heterostructure slot waveguide microcavity theoretically,which is a promising way to realize the high-efficiency luminescence of Si-based materials.
基金supported by the Ministry of Science and Technology of China (Grant No. 2007CB936204)the National Natural Science Foundation of China (Grant Nos. 61271050,61076057 and 61171023)
文摘In this paper,configuration parameters of the waveguide are altered independently or simultaneously to control the cutoff frequencies of the guided band.The independent control range of the upper and lower cutoff frequencies is 55.0% and 63.9% of the photonic band gap(PBG),respectively.The regulating range of the simultaneous tuning can be as large as 28.6% in terms of the PBG,or 240% in terms of the bandwidth.This tuning cutoff frequency method provides an efficient way to tailor the guided band and further tune the optical properties of PhCWs.
