Micro integrated planar optical waveguide type SPR Sensor.

An integrated optical waveguide type surface plasmon resonance (SPR) sensor having an optical waveguide with a corresponding SPR sensing area, photodetectors, and wave-length tunable laser or any kind of external tunable laser source/coupler formed on a substrate. In an embodiment, the laser is a wavelength tunable laser and optionally, the integrated device may include a power source on the substrate for providing a electric power to the wavelength tunable laser and the photodetectors, or a circuit for signal processing, or a microfluidic structure for routing a target sample to the SPR sensor area. The microfluidic structure optionally includes a mixer or a reaction chamber for mixing and allowing a physical or chemical reaction to occur, respectively. In an embodiment, plural planar integrated optical waveguide type SPR sensors may be fabricated on a substrate to form a array of SPR sensors

Area-Selective Disordering Of Multiple Quantum Well Structures And Its Applications To All-Optical Devices

A technique of impurity-free vacancy-induced disordering of GaAs/AlGaAs multiquantum wells (MQW) that is area selective, very reliable, and highly reproducible, has been developed. The localized compositional disordering is induced by rapid thermal annealing of the sample after it has been coated with a thin film of \u27\u27spin-on\u27\u27 glass and prebaked at 400 degrees C in a high purity nitrogen:oxygen (78:22) atmosphere. In order to self-consistently determine the diffusion coefficient of the Al and Ga atoms, the photoluminescence peak is fitted to the n=1 electron to heavy hole transition that corresponds to an error function potential profile caused by the diffusion. The process has been used to integrate two optical devices on a MQW structure. One is a nonlinear directional coupler all-optical switch, and the other is an integrated Mach-Zehnder all-optical modulator. The switching characteristics of the devices were measured using the conventional pump-probe measurement technique

Tunable Laser Diode Using Partially Intermixed Ingaasp Multiple Quantum Well

In this work, a two-section wavelength tunable laser diode is demonstrated using an InGaAsP multiple quantum well heterostructure. The laser diode consists of two sections with different bandgap energies achieved using selective area intermixing of the MQW. Using plasma enhanced chemical vapor deposition (PECVD), half of the sample is coated with a 30nm silicon nitride (SiNx) film followed by a 200nm thick overlay of silicon oxynitride (SiOxNy) film over the entire sample. The whole sample is then thermally annealed at 750°C for 30s, and that results in the SiOxNy covered section experiencing a narrowing of the bandgap energy, while leaving the SiNxcovered section practically unchanged. A laser stripe is fabricated that passes through both MQW sections. The wavelength of laser operation can then be tuned by varying the injected current levels applied separately to the two sections. The obtained tuning range was 40 nm spanning from 1538 nm to 1578 nm

Monolithically Integrated All-Optical Switch Using Quantum Well Intermixing

We report the realization of a compact monolithically integrated all-optical switch using selective area bandgap tuning of a multiple quantum well structure by impurity-free vacancy induced disordering technique. A 3-dB waveguide coupler was fabricated in the disordered section of the switch device. All-optical wavelength conversion at 1Gb/s was demonstrated. © Springer 2006

Monolithic quantum-well-tunable laser based on optical beam steering and area-selective intermixing

A monolithic tunable laser on a quantum well (QW) structure is demonstrated by integrating an optical beam-steering section with an area-selectively intermixed QW gain section. Wavelength tuning is achieved by guiding an amplified optical beam over an optical gain medium that consists of three laterally adjacent regions containing a quantum well that has been selectively intermixed to varying extents. The laser light output can be tuned over a total of a 17-nm wavelength range by separately injecting electrical current pulses to each of the two parallel contacts in the steering region and to the optical amplifier contact. (C) 2013 Society of Photo-Optical Instrumentation Engineers (SPIE

Liquid Sensor Based On Optical Surface Plasmon Resonance In A Dielectric Waveguide

In this work, we have demonstrated an optical surface Plasmon resonance (SPR) sensor head that is based on an inverted rib dielectric waveguide, in which the resonance wavelength of the surface plasmon excited at the gold metal-dielectric interface changes in relation to changes of the environment at the top metal surface. The inverted-rib waveguide of the SPR sensor head is made of a layer of SU-8 polymer with a refractive index of 1.5 while the lower cladding layer consists of silicon oxynitride (SiOxNy) with a refractive index of 1.526. The top surface is coated with a 50 nm thick layer of gold. The SPR sensor head was designed to allow monitoring of analyte media with a refractive index ranging from 1.44 to the 1.502. Using a set of reference liquids representing the analyte medium, the sensitivity of the SPR sensor was measured using a broadband light source and a optical spectrum analyzer. It was found that with a liquid of 1.442 refractive index in contact with the gold metal, a sharp resonance dip in the transmission spectrum occurred at 1525 nm and its position shifted to 1537 nm when a liquid of 1.502 was used. From these measurements, the sensitivity of the sensor devices wasdetermined to be S = 232 nm.RIU-1. We demonstrate that this device can potentially be totally integrated with a wavelength tunable light source, a photodetection unit as well as a liquid delivery system via microfluidic channels making it an extremely compact unit

All-Optical Switching And Wavelength Conversion Using Passive Nonlinearities In Semiconductor Quantum Wells

A silica capped impurity-free vacancy induced disordering has been used in the fabrication of an all-optical integrated Mach-Zehnder switch incorporating a linear waveguide directional coupler with nonlinear multiple quantum well (MQW) sections. Using the switch we have been able to demonstrate all-optical wavelength conversions at a rate of 1 GHz that was limited by our laser source, a modelocked erbium doped fiber laser. In principle the device performance is expected to be undiminished up to repetition rates of 10Gb/s and higher