Float-glass: An industrial substrate for integrated optics

Low-loss single-mode waveguides form at the surface of glass in contact with liquid tin during the float process. Theoretical and experimental studies have demonstrated that float-glass can serve as an industrial substrate for integrated optics.     

Transformation optics and infrared metamaterials for optical devices

The coordinate transformation approach is applied for the design of an optical mode adaptor between two different width waveguides in the near IR telecom optical domain. The control of the mode profile in the adaptor is achieved by considering a composite waveguide consisting of a thin metamaterial (MM) layer intercalated between 2???m thick SU8 photoresist slab and a glass substrate. We demonstrate that intercalated metafilm enables the realization of a space coordinate transformation and allows a precise control of the light propagation in the composite waveguide. Numerical simulations and experimental realizations of the metamaterial layer are performed in order to validate the device concept and realization feasibility.     

原子光学讲座第一讲几何与波动原子光学及其器件

文章首先简单介绍了冷原子操纵与控制的基本原理。然后，重点介绍了几何与波动原子光学及其器件的研究内容、潜在应用和最新进展，其中包括：原子束的反射和原子反射镜；原子束偏转（折射）、聚焦成像和原子透镜；原子衍射和原子光栅；原子干涉和原子干涉仪；原子全息学及其技术等。     

Fold optics path: an improvement for an atomic fountain

A fold optical path is utilized to capture and launch atoms in the atomic fountain.This improved technique reduces the laser power needed by 60 percent,facilitates suppression of the laser power fluctuations,and leads to a more simple and stable system.     

Multilayer polymeric mode and polarization filters for integrated optics

We demonstrate theoretically as well as experimentally that a four-layer polymeric waveguide structure can be used to produce a mode and a polarization filter. Various optical properties such as refractive index, birefringence and propagation constant of polycarbonate, polystyrene and a commercially available photoresist (from Shipley) are presented. The thin film structures consisting of glass/polycarbonate/polystyrene/air are used for demonstrating polarization filter action and glass/photoresist/polystyrene/air structure for mode filter. Expressions for the electric field intensity spatial distribution for the structure are used to calculate the intensity profiles to support the observed behavior. The experimental values were in good agreement with the one obtained theoretically.     

Extreme events in optics: Challenges of the MANUREVA project

In this contribution we describe and discuss a series of challenges and questions relating to understanding extreme wave phenomena in optics. Many aspects of these questions are being studied in the framework of the MANUREVA project: a multidisciplinary consortium aiming to carry out mathematical, numerical and experimental studies in this field. The central motivation of this work is the 2007 results from optical physics [D. Solli et al., Nature 450, 1054 (2007)] that showed how a fibre-optical system can generate large amplitude extreme wave events with similar statistical properties to the infamous hydrodynamic rogue waves on the surface of the ocean. We review our recent work in this area, and discuss how this observation may open the possibility for an optical system to be used to directly study both the dynamics and statistics of extreme-value processes, a potential advance comparable to the introduction of optical systems to study chaos in the 1970s.     

Partially and fully cured thin film photoresist waveguides for integrated optics

A systematic and detailed study of waveguide fabrication and characterization of a commercially available (from Shipley) photoresist is reported. Various waveguide properties such as refractive index, optical losses, waveguide thickness, dispersion and birefringence are reported. Effect of temperature of guide formation, curing (partial and full) and UV exposure on these parameters is also presented.     

A diagrammatic method for analysis of GaAs and InP based optoelectronic devices

A modified version of the signal flow graphs method can be applied to reveal the topological structure of physical models describing the operation of optoelectronic devices based on heterostructures comprising A^IIIB^V semiconductor compounds. In particular, this kind of analysis is apt to reveal the presence of closed paths (feedback loops) in the causal make-up of the phenomena underlying function of the devices. The analytical apparatus associated with the diagrams affords a new formulation of criteria for the occurrence of such physical conditions as the bistability or the threshold behaviour. The approach is illustrated on the instances of injection semiconductor laser, nonlinear Fabry-Perot resonator, self-electro-optic effect device and semiconductor laser optical amplifier. Presented at the 1st Czech-Chinese Workshop “Advanced Materials for Optoelectronics”, Prague, Czech Republic, June 13–17, 1998 Support of the Grant Agency of the Czech Republic (project No. 102/99/0341) is gratefully acknowledged.     

New silicon-based fibre assemblies for applications in integrated optics and optical MEMS

Nearly closed rhombus-shaped channels in micromachined silicon with very high accuracy for fibre array assemblies are presented. The fabrication and the assembly of fibres are described. The achieved accuracy is comparable with conventional V-groove assemblies. Additionally, rhombus-shaped channels allow new applications such as monitor pigtails with integrated photodiodes or buried fibre supplies in optical MEMS. Received: 22 May 2001 / Revised version: 7 September 2001 / Published online: 30 October 2001     

Modeling and simulation of multiple resonant Lorentz dispersive materials for integrated optics

Complex materials are of increasing interest in Finite-Difference Time-Domain (FDTD) modeling. For example, when the particle density becomes large, collisional fluid models of plasmas are an attractive alternative to particle in cell methods. Further, frequency dispersive meta-materials are of increasing interest. Thus, Finite-Difference Time-Domain (FDTD) models are derived for magnetized plasmas and for the Lorentz and Drude material models. This paper models the Lorentz material using the FDTD tool. The modal analysis and various types of simulation results are also presented for these materials.     

Design, simulation and characterisation of integrated optics for a microfabricated flow cytometer

Flow cytometry is widely used for analyzing micro-particles such as cells and bacteria. Microfabricated flow cytometers promise reduced instrument size and cost with increased robustness and have application in medicine, life sciences and environmental metrology. Further miniaturisation and robustness can be achieved if integrated optics are used instead of traditional free space optics. We present designs simulation and experimental characterisation of integrated optics for a microfabricated cytometer made from SU-8 resin on a glass substrate. The optics constructed from combinations of optical fibres (positioned with microgrooves), waveguides, and microlenses enable analysis of scattered light and fluorescence from particles positioned near the centre of a microchannel using one dimensional sheath flow. Four different methods for directing the incident light onto the particles are examined and the optimum design discussed.     

Fabrication and application of imaging holographic gratings (chirped gratings) for integrated optics

Holographic chirped gratings with parallel grating lines have been fabricated by recording the interference structure of a plane wave and a cylindrical wave in a photoresist layer on a monomode glass waveguide. These gratings will be useful elements for the imaging of guided waves in integrated optics. A theoretical approach for treating their imaging properties is presented. The experimental results are described theoretically.     

A perturbation technique to model InGaAs/InP and GaAs FETs for millimeter-wave integrated circuits

A perturbation method is described to analytically model the electrical behavior of submicron FETs for millimeter-wave circuit applications. The approach includes the determination of the two-dimensional potential distribution in a non-rectangular depletion region. The result is used to derive analytical expressions for the threshold voltage and transconductance of FETs.     

电液伺服综合试验机的修复改造

为了解决电液伺服系统因使用年限太久,各模块出现不同程度的老化,且操作界面不友好导致系统不能正常运行的现状。现提出了对原有的电液伺服试验机进行改造,替换原系统的控制设备和数据采集设备,更新原系统的软件,设计一种新型电液伺服综合试验机系统。应用下位机PLC作为控制器替代原系统的ISA接口控制板,连接上位机LabVIEW作为显示界面为动静态实验提供详细的资料。对改造后的系统进行了钢板弹簧试验检测,并对检测结果进行分析,各试验数据在电液伺服试验机国家标准允许的误差范围内,试验结果表明检测系统稳定性好,控制性高,使用方便及可靠有效。     

含超导磁储能装置的电力系统关键技术研究

超导磁储能系统(SMES)因其响应速度快,能够灵活地对有功、无功功率进行独立控制等特点,在电力系统中具有良好的应用前景。简要介绍了超导磁储能装置的应用现状;从装置及系统两个层面分析了SMES应用的关键技术问题;结合新能源发电及新型用电负荷探讨了SMES未来的应用场景。     

测量液体和气体折射率的集成光学技术单侧和双侧漏模法

由单侧和双侧漏模法,测量了液体和气体的折射率,将液体或气体滴入或充入棱镜和衬底之间,使这三层介质组成单侧或双侧漏波导.用棱镜耦合器测量共振漏模的模折射率,并由相应的模方程确定液体或气体的折射率.测量结果表明,折射率的误差为1～3×10~(-4).并在理论上对测量精度作了分析和讨论.     

Ensembles of indium phosphide nanowires: physical properties and functional devices integrated on non-single crystal platforms

A new route to grow an ensemble of indium phosphide single-crystal semiconductor nanowires is described. Unlike conventional epitaxial growth of single-crystal semiconductor films, the proposed route for growing semiconductor nanowires does not require a single-crystal semiconductor substrate. In the proposed route, instead of using single-crystal semiconductor substrates that are characterized by their long-range atomic ordering, a template layer that possesses short-range atomic ordering prepared on a non-single-crystal substrate is employed. On the template layer, epitaxial information associated with its short-range atomic ordering is available within an area that is comparable to that of a nanowire root. Thus the template layer locally provides epitaxial information required for the growth of semiconductor nanowires. In the particular demonstration described in this paper, hydrogenated silicon was used as a template layer for epitaxial growth of indium phosphide nanowires. The indium phosphide nanowires grown on the hydrogenerated silicon template layer were found to be single crystal and optically active. Simple photoconductors and pin-diodes were fabricated and tested with the view towards various optoelectronic device applications where group III–V compound semiconductors are functionally integrated onto non-single-crystal platforms.     

Simple interference method of diffraction grating generation for integrated optics by the use of a Fresnel mirror

A very simple and compact arrangement is proposed for generation of surface periodic structures for integrated optics using laser exposition and photolithographic technique. The method applied is based on the division of a laser beam into two “half-wavefronts” by a Fresnel mirror (90°) with one arm formed by an exposed sample, and on interference of divided wavefronts on the sample surface.