Polarization-insensitive planar lightwave circuit dual-rate Mach-Zehnder delay-interferometer

We demonstrate a silica waveguide Mach-Zehnder delay-interferometer that uses integrated switches to demodulate either 10- or 40-Gb/s differential phase-shift keyed signals. We achieved polarization insensitivity by using a half-wave plate and reducing polarization crosstalk in the couplers.     

Highly-integrated planar lightwave circuit wavelength selective switch

The first demonstration of large-scale integration of AWG filters and thermo-optic switches and attenuators in 2% delta silica-on-silicon waveguides is reported. A compact high performance wavelength selective switch is demonstrated.     

Dynamic wavelength tuning of channel-drop device in two-dimensional photonic crystal slab

Dynamic and external tuning of the operating wavelength of a channel add/drop device based on a two-dimensional photonic crystal slab is demonstrated. Thermo-optical effect, where the temperature increase is induced by the absorption of external light, is utilised for the tuning. The tuning speed is shown to be as fast as 20 /spl mu/s.     

Designs and experiments on infrared two-dimensional silicon photonic crystal slab devices

Photonic crystal (PhC) has offered a powerful means to mold the flow of light and manipulate light-matter interaction at subwavelength scale.Silicon has a large refraction index and low loss in infrare...     

Lattice-form CWDM interleave filter using silica-based planar lightwave circuit

We demonstrate an eight-channel coarse wavelength-division-multiplexing interleave filter that employs a silica-based lattice-form filter. The filter incorporates phase-generating couplers to convert a conventional frequency interleave filter into a wavelength interleave filter with a constant channel spacing with respect to wavelength. We fabricated the designed interleave filter on a 1.5%-/spl Delta/ silica-based waveguide and realized a constant channel spacing of 20 nm with a wavelength displacement of within /spl plusmn/0.5 nm and an insertion loss of less than 1.7 dB over eight channels.     

Low-loss planar lightwave circuit OADM with high isolation and nopolarization dependence

A passive optical add-drop multiplexer with 1 dB of insertion loss and 36 dB of isolation is fabricated by writing Bragg gratings in a waveguide Mach-Zehnder interferometer using ArF excimer laser light. The spectral properties and bit-error-rate performance of the device are fully characterized using polarized light     

Guided-wave laser based on erbium-doped silica planar lightwave circuit

The Er-doped silica guided-wave laser operating around 1.6 mu m was realised using a low-scattering-loss planar lightwave circuit with an Er-doped silica core which was fabricated by flame hydrolysis deposition and reactive ion etching techniques on an Si substrate. CW lasing was achieved successfully with an incident threshold power of 49 mW for pumping at 0.98 mu m.<>     

WDM-PON module using a planar lightwave circuit with a coated WDM filter

We have presented a new configuration of a planar lightwave circuit (PLC) module coated directly with a filter which divides 1310/1550-nm wavelength bands for a wavelength-division-multiplexing passive optical network module in order to improve the conventional insertion process of thin film filter into the narrow trench located at the Y-junction of a PLC platform. The broadly tapered output facet width of a V-shaped waveguide was designed to be 12 /spl mu/m to minimize the reflected loss. The receiver module integrated with a PIN-photodiode on a silicon optical bench was fabricated. Data transmission of 2.5-Gb/s was demonstrated with clear eye diagrams.     

二维光子晶体中的自准直研究

利用平面波展开法计算了二维三角晶格的光子晶体的色散关系,分析了第一条带的等频率线,利用时域有限差分法仿真显示了第一条带具有较好的自准直现象特性.在此基础上,设计了一种可以使得光在无缺陷光子晶体中改变传播方向的结构,并对此结构进行了实验仿真.     

平板型光子晶体液晶微谐振腔的温度特性

在二维光子晶体薄板的中心空气孔中填充厚度与光波长相当的液晶材料,形成平板型光子晶体液晶微谐振腔结构。用时域有限差分法研究了液晶微谐振腔的温度特性,并用Matlab编程进行了数值计算。计算结果表明,由于液晶折射率是温度的函数以及微腔对光波传输的约束,当温度升高时微谐振腔的透射峰波长向长波长方向移动,透射峰半高宽度减小,品质因子增大,谐振波长和品质因子随填充因子与平板厚度的变化曲线向增大方向移动,接近液晶相变点时微腔的温度特性变化更迅速。平板型光子晶体液晶微谐振腔的温度特性,为可调光子晶体器件的设计提供了理论基础。     

单纤三向器件平面光波导芯片结构优化设计

文章对采用平面光波导技术的单纤三向器件(Triplexer)芯片结构的参数进行了优化设计,对单元结构的光谱响应进行了模拟计算,通过数值模拟分析了结构的工艺容差性.结果表明,采用双模耦合器和M-z干涉仪结构可以得到工艺容差性高、光谱响应优良的适用的Triplexer器件.     

Tunable edge-emitting microlaser on photonic crystal slab

A tunable edge-emitting microlaser is realised by a chirped line-defect photonic crystal waveguide. A tunable range of 57 nm is obtained experimentally.     

Wideband planar lightwave circuit type variable optical attenuator using phase-generating coupler

A novel wideband planar lightwave circuit type variable optical attenuator (VOA) that incorporates a phase-generating coupler is proposed. The proposed VOA was fabricated on a 1.5%-/spl Delta/ silica-based waveguide, and obtained a low insertion loss of less than 1.2 dB and a low wavelength dependent loss of less than 0.8 dB at attenuation levels of 0 to 25 dB over the C- and L-band wavelength range.     

Simple method for mitigation of polarization crosstalk in silica planar lightwave circuit directional couplers

Polarization crosstalk in planar lightwave circuit directional couplers can cause significant polarization-dependence in interferometers that use them. We show a simple way to mitigate the polarization crosstalk without incurring a performance penalty or requiring extra fabrication steps. We demonstrate it on a 23-ps Mach-Zehnder delay interferometer.     

Laser-diode pumping of waveguide laser based on Nd-doped silica planar lightwave circuit

The authors describes an improvement in the lasing threshold in Nd-doped silica planar-lightwave-circuit (PLC)-type lasers fabricated on Si substrates in which the scattering loss was reduced by an improved fabrication technique. Lasers with core widths from 6 to 30 mu m were fabricated by flame hydrolysis deposition and reactive ion etching techniques. Based on an investigation of the lasing threshold dependence on core width, a minimum lasing threshold was obtained in a waveguide laser with an 8 mu m wide core. A threshold of 25 mW and a slope efficiency of 1.2% for laser-diode pumping at 805 nm were obtained in the waveguide laser.<>     

Ultra-compact optical filter in two-dimensional photonic crystal

A design of an ultra-compact in-plane optical add/drop filter is proposed. The filter is formed by two waveguides and one two-mode cavity in a two-dimensional triangular photonic crystal. The simulated results demonstrate good transfer characteristics with a quality factor of about 1700.     

Design of photonic crystal fibers for dispersion-related applications

A general procedure for design of photonic crystal fibers (PCFs) with desirable dispersion properties is presented. The design model is based on the combination of a rigorous vector mode solver and a scaling transformation for the dispersion properties of the PCFs. In comparison with the conventional design method, the new design procedure is more efficient and can be readily automated for the purpose of design optimization. Several applications of the design procedure, e.g., the design optimization for dispersion shifted fibers, dispersion flattened fibers, and dispersion compensation fibers, are demonstrated and discussed.     

Highly linear-polarized external cavity lasers hybrid integrated on planar lightwave circuit platform

We propose and demonstrate, for the first time, a highly linear-polarized external cavity laser (ECL) integrated on planar lightwave circuit (PLC) with an in-PLC polarizer designed to improve polarization extinction ratio (PER). The in-PLC polarizer based on a 45/spl deg/-tilted grating was simply formed in the laser cavity composed of a Fabry-Pe/spl acute/rot laser diode and a Bragg grating. The proposed ECL exhibited a PER value as high as 30 dB and single longitudinal mode oscillation with a high sidemode suppression ratio of 50 dB at 1310 nm.     

Encoder/decoder on planar lightwave circuit fortime-spreading/wavelength-hopping optical CDMA

A planar lightwave circuit-based encoder/decoder for time-spreading/wavelength-hopping optical code division multiple access (CDMA) that consists of an arrayed-waveguide grating and variable delay lines is proposed. Its flexible code assignment operation and auto-/cross-correlations at 10 Gbit/s is confirmed     

Single-mode operation of two-dimensional photonic crystal laser with central post

Two-dimensional slab photonic crystal lasers with central posts are realized. In this structure, those modes with antinode at the center are suppressed by the presence of the central post. From a five-lattice-long photonic crystal cavity, single-mode operation is experimentally observed. Thermal characteristics are drastically improved in comparison to those of the free-standing slab structure.