复周期结构光子晶体的光子能带特性研究

本文构思了一种每个周期内部有几个不同的小单元的复周期结构光子晶体，并利用光学传输矩阵法对这种光子晶体进行了数值模拟计算。计算结果表明，这种复周期结构光子晶体比普通结构的光子晶体多出1个大的光子禁带区。适当调整参数还可以分别获得多通道窄带滤波特性、带通滤液特性和窄带透过特性。     

Study of whispering-gallery-mode in a photonic crystal microcavity

The whispering-gallery-mode (WGM) photonic crystal microcavity can be potentially used for miniaturized photonic devices, such as thresholdless lasers. In this paper, we use plane wave expansion (PWE) method and study the WGM of H2 photonic crystal microcavities which are formed by removing seven center air holes in a photonic crystal. The WGM in these large-size cavities has some advantages compared with single defect WGM in the view of real device applications. We analyze the nearby air hole e...     

带有环形谐振器的T形光子晶体滤波器

提出了一种带有环形谐振器的T形光子晶体滤波器,利用时域有限差分法研究了滤波器传输特性,分析了光子晶体结构参数对其传输特性影响。结果表明：该结构具有可调性开关波长、传输率高及频带宽的特点,在光子晶体集成制作、光通信器件制作等方面具有潜在的应用价值。     

Fabrication of a polymeric photonic crystal wavelength splitter using ultra violet embossing technology

We present the design concept and the possibility of UV embossing technology for polymeric photonic crystal functional devices. Our design concept for polymeric photonic crystal devices is to utilize quasi self-collimating effect of photonic crystal, showing a light propagation with poor divergence in photonic crystal region, and a wavelength dependence of light propagation direction in this region. It is possible to realize various functional devices with ultra compact size using photonic crystal, even in the polymeric material with low optical index, as it does not use the photonic bandgap directly. The fabricated final replica has almost no residual polymer, since the use of UV curable polymer with low viscosity and an additional ashing process. These design concept and fabrication technique are quite appropriate to be utilized for mass production of economical optical integrated circuits.     

Design and characterization of a 120-GHz millimeter-wave antennafor integrated photonic transmitters

We developed a planar slot antenna on an Si substrate for a photonic >100-GHz millimeter-wave (MMW) transmitter. We designed the antenna by using three-dimensional electromagnetic-field simulators and characterized its performance by using an optoelectronic network analyzer. The transmitter uses a very fast photodiode with high output power. Using these photonic techniques, we succeeded in building this compact photonic transmitter that emits MMWs with a power of >0.2 mW at a frequency of 120 GHz     

Lithographic tuning of a two-dimensional photonic crystal laserarray

One attraction of photonic crystals is the ability to control optical device characteristics by lithographically varying the geometry. In this letter, we demonstrate a 10×10 array of optically pumped two-dimensional (2-D) photonic crystal defect lasers with varying lattice parameters. By adjusting the photonic crystal interhole spacing as well as the hole diameter we are able to tune the laser wavelength from 1500 to 1625 nm on a monolithic InP-InGaAsP wafer. A wavelength resolution of 10 nm from device to device was obtainable, limited by the lithography and etching tolerances of our fabrication method     

Microwave Correlator Based on a Nonuniformly Spaced Photonic Microwave Delay-Line Filter

We propose and demonstrate a novel technique to perform matched filtering of a phase-coded microwave signal using a photonic microwave delay-line filter. The photonic microwave delay-line filter is designed to have a frequency response that is conjugate to the spectrum of the phase-coded microwave signal. To implement the delay-line filter, the tap coefficients are usually complex, which is difficult to implement in the optical domain. In this letter, a photonic microwave delay-line filter with equivalent complex coefficients implemented using an all-positive- coefficient photonic microwave delay-line filter based on a nonuniformly spaced delay-line structure is proposed. Since only positive coefficients are required, the implementation of the filter is greatly simplified. An experiment is performed. The decoding of a 6.75-GHz binary-phase-coded microwave signal is experimentally demonstrated.      

Microwave Photonic Signal Down‐Conversion Using a Novel Two‐Frequency Bragg Grating Based Brillouin Fiber Laser

A simple technique using a novel two‐frequency Bragg grating based Brillouin fiber laser to down‐convert high frequency microwave photonic signals is presented. The mechanism of the Brillouin fiber laser and the principle of this technique for microwave photonic signal down‐conversion are analyzed. The 12GHz microwave photonic signals are experimentally down‐converted to 1.13GHz IF signal with the technique.     

高非线性石英基光子晶体光纤产生宽带可调中红外孤子的实验研究

通过研究发现双包层结构能降低石英基光子晶体光纤损耗,并制备一种高非线性双包层结构石英基光子晶体光纤来进行实验研究.使用钛宝石飞秒激光器将实验室自制的石英基光子晶体光纤在反常色散区泵浦,研究不同的泵浦功率和泵浦波长对中红外超短脉冲孤子的影响,并分析了石英基高非线性光子晶体光纤中红外超短脉冲孤子产生的物理机理.结合实验发现在泵浦功率为827 nm,功率从0.1 W增加到0.42 W时,中红外第一个孤子随功率增加从1933 nm移动到2403 nm,可调范围达到470 nm,为石英基光子晶体光纤产生宽带可调超短脉冲源创造了很好的条件.     

Nanofabrication of 1-D photonic bandgap structures along a photonic wire

A strongly-guided one-dimensional (1-D) waveguide called a photonic wire has high spontaneous emission coupling efficiency, enabling one to realize low-threshold lasers. Combined with the use of 1-D photonic bandgap structures consisting of arrays of holes etched within the photonic wire, novel microcavity lasers can be realized. We report the nanofabrication of a photonic bandgap structure for 1.5 /spl mu/m wavelength along a InGaAsP photonic wire, and discuss numerical simulations for its electrodynamics.     

Demonstration of the highly reliable Hikari router network based on a newly developed disjoint path selection scheme

Integration of multiprotocol label switching functions and multiprotocol lambda switching functions can enhance the throughput of IP networks and remove bottlenecks that are derived from electrical packet processing. To enhance the packet forwarding capability, NTT proposed a photonic MPLS concept that includes MP/spl lambda/S, and demonstrated IP, MPLS, and photonic MPLS integrated router systems called the photonic MPLS router. This router system is now called the Hikari router. The word Hikari is Japanese meaning beam, light, lightwave, optical, photonic, and sunshine. The amount of IP data traffic has grown remarkably. Massive IP routers and flexible route control mechanisms are now required to cope with the increased amount of traffic. The Hikari router can offer two solutions utilizing photonic switching technologies, and photonic network operation and management technologies. The first solution is utilizing photonic switching technologies realized using optical-switch-based crossconnect systems. The other solution is realized using the MPLS and MP/spl lambda/S signaling protocol and photonic network protection functions. In this article we report on the implementation of the Hikari router systems, propose a newly developed disjoint path selection scheme for generalized MPLS networks with shared risk link group constraints, and demonstrate the signaling protocol and network protection functions. The demonstration system achieves a distributed optical path set-up/tear-down protocol with an extended constraint-based routing label distribution protocol. Fast self-healing through automatic protection switching and a new restoration scheme are also implemented. These functions are successfully implemented, and the performance is verified on a demonstration network. The protection switching scheme achieves protection in less than 20 ms, and the optical path restoration scheme achieves restoration in less than 500 ms.     

Coherent microwave generation in a nonlinear photonic crystal

We propose a new approach for generating coherent microwaves in a nonlinear photonic crystal through optical rectification. In a photonic crystal, the reciprocal vector and dispersion of the group velocity can be used to both compensate for the velocity mismatch between the generated microwave and the pump light. We show that coherent microwave radiation from kilohertz to terahertz can be generated through this approach by designing a suitable structure     

Study on a novel photonic crystal temperature sensor

In this paper, a model of photonic crystal temperature sensor based on crystal microcavity in a straight photonic crystal waveguide is proposed. The transmission characteristics of light in the sensor under different temperatures are simulated by using finite-difference time-domain (FDTD) method. The thermal expansion and thermal-optic effects of silicon are taken into account. The results show that the resonant wavelength of microcavity increases linearly as the temperature rising. The waveleng...     

一种新型微波光子器件--多量子阱光-微波转换器的设计构想

最近十年,微波光子领域的研究在世界范围内吸引了越来越多的兴趣,作为微波光子器件系列的光-微波转换器,扮演了重要的角色。本文提出了一种新型的多量子阱超宽带光-微波变换器的设计构想,介绍了其结构、功能并进行了分析。     

带有环形谐振器L型弯折光子晶体波导性能的研究

本文提出了一种带有环形谐振器的L型弯折光子晶体波导结构,利用时域有限差分法研究了该波导电磁波的传输性能.分析结果表明:该结构具有宽频带、高传输率等特点,在光通讯器件制作、光子晶体集成化等方面具有潜在的应用价值.     

内嵌结构光子晶体在F 型微带天线中的应用

对常用的正方晶格光子晶体结构进行改进优化,设计出一种新型内嵌结构式二维光子晶体,即在普 通正方晶格光子晶体内部嵌入同类晶格的光子晶体。将该结构光子晶体应用到F 型微带天线中,采用平面波展开 法,进行大量仿真计算。结果表明:与传统的微带天线相比,加入该结构光子晶体后的微带天线回波损耗由 -18. 2465dB 降低到-41. 0624dB。天线具有更好的阻抗特性和辐射效率,方向图有所改善,背瓣辐射最大处减少约 5dB。这种新型的光子晶体微带天线达到了提高天线性能的目的。     

Photonic band gap of the photonic crystals with chiral and negative-index materials

In this paper, the photonic band gap of photonic crystals with chiral and negative-index materials alternately is investigated. It is shown that this kind of photonic crystal exhibits very wide photonic band gap. The photonic crystals with a defect layer have a narrow defect mode in the band gap, which can be used as a very good filtering material by choosing the parameters of the defect layer properly.     

光子晶体线缺陷波导中的慢光研究

研究了线缺陷光子晶体波导中的慢光现象。运用平面波展开法对线缺陷光子晶体波导结构进行了模拟计算,分析了填充因子作为敏感结构参量,其变化对色散性质和群速度的影响。发现光子晶体的填充因子决定了光子晶体带隙中导模的传输特性。随着填充因子的增加,光子晶体波导中的群速度先增大再减小。可以证明,通过改变光子晶体的填充因子,群速度可以达到0.01c以下。     

Lasing band-edge identification for a surface-emitting photonic crystal laser

The possibility of single-mode oscillation over a large cavity area for photonic crystal lasers emitting at the photonic band edge has resulted in much interest in such materials for new forms of solid-state laser. In this paper, we measure the photonic bandstructure in our sample and identify the lasing band edge. By mapping out the bandstructure at the /spl Gamma/-point, we have observed fine structure at the band edge. The experimental results are in good agreement with the theoretically predicted bandstructure. Above threshold, we observe a lasing peak at 965 nm at one of the band edges. The far-field distribution of the laser is measured, showing an annular profile and azimuthal polarization. Calculations on the far-field distribution at the lasing band edge suggest the annular profile is due to an anti-symmetric resonant mode.     

一种新型光子晶体的光学特性研究

本文提出了一种非对称一维各向异性掺杂光子晶体,通过传输矩阵法研究了这种新型光子晶体的光学特性,通过数值模拟得出:光通过该结构光子晶体后TE波和TM波缺陷模的透过率及中心波长位置随缺陷层介质的光学厚度、缺陷层两侧周期数的非对称性的变化规律,两种偏振光波能完全分开,缺陷层介质的光学厚度及掺杂层两侧的周期数层差越大,缺陷模的透过率越小,当光学厚度及层差达到某一极限值时,将产生完全光子禁带,这是对称结构光子晶体所不具备的光学特性,其光学特性将为光子器件的转换制作及应用提供理论依据。