Barium strontium titanate (Ba0.05Sr0.95TiO3) ferroelectric thin films have been prepared on single crystal [001] MgO substrates using the pulsed laser deposition method. The X-ray diffraction (XRD) analysis show the films were oriented with the [001] direction perpendicular to the plane of the substrate. The refractive index of Ba0.05Sr0.95TiO3 is determined from model fitting with the calculated data of the reflectivity of Ba0.05Sr0.95TiO3 in the wavelength 1450-1580 nm at the room temperature. The dispersion curve decreases gradually with increasing wavelength. The average value of the refractive index is found to be 1.985 in the wavelength 1450-1580 nm which is important for optoelectronic device applications.

This Letter reports the use of an inductively coupled plasma technique for fabrication of proton-exchanged (PE) LiNbO3 (LN) waveguides. Planar and stripe waveguides have been formed in Y-cut LN which are difficult to obtain with the conventional molten acid method due to the occurrence of surface damage. Secondary ion mass spectrometry, scanning electron microscopy, and infrared absorption spectrum characterization results revealed that a uniform vertical PE profile with a single low order crystal phase has been directly obtained as a result of this unique process. X-ray photoelectron spectroscopy characterization of the treated surface revealed the existence of NbO as the cause for a sometimes darkened surface and confirms the ability to completely restore the surface to LN by oxygen plasma treatment. Atomic force microscopy measurement confirms that good surface quality has been maintained after regeneration of the surface to LN.

We demonstrate the use of an integrated 4 /spl times/ 4 InGaAsP-InP active vertical coupler optical crosspoint switch matrix to detect optical labels and to further switch variable length optical packets at rate of 10 Gb/s. Label detection sensitivity is assessed. Switched payload Q-factor and power penalty measurements have been carried out. Power penalty of less than 1.5 dB is found.

Dynamic per-packet output power equalization is demonstrated in a 4 /spl times/ 4 active vertical coupler-based optical crosspoint packet switch, achieving response time of <100 ns and output power levels within /spl plusmn/0.3 dB for input dynamic range of 5 dB between consecutive optical packets.

Multicasting packet-switching characteristics are achieved with an integrated 4/spl times/4 optical crosspoint switch matrix based on active vertical coupler switch cells. Q-factor analysis confirms the flexibility of such a device to perform different kinds of optical packet switching applications.

This paper describes a fully packaged 4x4 optical crosspoint switch (OXS) device and several of its application demonstrations. The core switch chip is based on Bristol’s unique active vertical coupler (AVC) switching technology. The 4x4 switch is pigtailed with 4-fibre lensed arrays using a Si V-groove technique. The packaged device is further interfaced via an electronic decoder/driver circuitry. Several novel experimental demonstrations are carried out, including optically addressed optical uni-cast routing, optical multicast routing, and packet level automatic gain control (AGC). These experiments highlight the unique performance and versatility of the AVC OXS device.

This paper analyse a novel optical multicast scheme without excess optical splitting loss realised using an active vertical coupler based optical switch matrix utilising optical gain in the AVC switch cells. Theoretically analysis and computer simulation are carried out regarding the operational principle and switching characteristics of this scheme. Computer simulation suggests that the amplified spontaneous emission limited scalability of the scheme can be as high as more than 40. Experiment investigation of the predicted multicast switching operation using existing 4x4 switch matrix device has been carried out in for single wavelength and WDM signals. Multicast scale up to 2x4 is demonstrated. Measured switching characteristics and the OSNR values are in good agreement with simulation predictions. High Q factor values for 1-to-4 and 2-to-4 multicasting switched signals indicate that the scale of the multicasting scheme can be further increased.

Dynamic per-packet output power equalisation is demonstrated in an optical crosspoint packet switch, achieving response time of <100 ns and output power levels within ±0.3 dB for IPDR of 5 dB between consecutive optical packets.

This paper investigates a novel optical multicast scheme without excess optical splitting loss to be realized using an active vertical coupler (AVC)-based optical switch matrix, due to the optical gain available in the AVC switch cells. Theoretical analysis and computer simulation have been carried out regarding the operational principle and switching characteristics of this scheme. Computer simulation further suggests that the amplified spontaneous emission (ASE)-limited scalability of the scheme can be as high as more than 40. Experiments using an existing 4 /spl times/ 4 switch-matrix device successfully demonstrated the predicted multicast switching operation. Measured switching characteristics and the optical signal-to-noise ratio (OSNR) values are in good agreement with simulation predictions. High switched-signal Q-factor values of 1-to-2 and 1-to-3 multicasting configurations indicate that the scale of the multicasting scheme can be further increased significantly.

It has been experimentally demonstrated that an intensity modulated optical label at 155 Mbit/s can be detected directly by a 4 x 4 optical crosspoint switch without added optical components. Further routing of 10 Gbit/s packets can be performed without being affected by the label detection process, with a payload transmission power penalty of less than 1.5 dB.

This paper describes a packaged and fiber array coupled 4 x 4 optical crosspoint switch designed for optical packet switching. Alignment and fixation techniques of two perpendicular fiber arrays to the integrated InP-based switch chip have been developed. Thermal management is also included in the packaging. The packaged devices demonstrate long-term stability and have been used in switch modules, including the packaged device and electronic interfaces.

The integration of a low cost VCSEL with a microstrip antenna results in a low cost wireless-optical transmitter. The VCSEL impedance is matched to that of the antenna and initial microwave link results are shown

The integration of a low cost Vertical Cavity Surface Emitting Laser (VCSEL) with a microstrip antenna results in a low cost wireless-optical transmitter. The VCSEL impedance is matched to that of the antenna and initial microwave link results are shown. The VCSELantenna is then used as part of a fully bidirectional wireless optical link and data is successfully transferred between two wireless enabled laptops.

Two methods for focused ion beam (FIB) etching of photonic crystal are presented. The first is a FIB-alone approach which is a very rapid, maskless process. This method has the disadvantage that it produces poor sidewall verticality, which leads to high losses in slab waveguide based systems. A second approach uses FIB to etch a metal mask layer, this is followed by reactive ion etching (RIE) of a SiO/sub 2/ layer and a final inductively coupled plasma (ICP) etch of the InP layer. Results show much improved sidewall verticality.

Packet-switching characteristics are optimized across an integrated 4 /spl times/ 4 optical crosspoint switch matrix consisting of active vertical-coupler-based switch cells. Optical gain difference between the shortest and the longest paths less than 3 dB is demonstrated. Bit error rate (BER) and power penalty measurements during packet routing have also been carried out over the entire 4 /spl times/ 4 matrix. At a 10-Gb/s packet data rate, a less than 1-dB power penalty is observed across the switch matrix, and the possibility for error-free packet routing is demonstrated with no BER floor observed.

Packet-switching characteristics of an integrated 4 /spl times/ 4 InGaAsP-InP active vertical coupler optical cross-point switch matrix are optimized. Optical gain differences of less then 3 dB between the shortest and longest switching paths are achieved. Bit-error rate (BER) and power penalty measurements during packet routing have been carried out over the entire 4 /spl times/ 4 matrix. At 10-Gb/s packet data rate less than 1-dB power penalty is found across the switch matrix, and the possibility for error-free packet routing is demonstrated with no BER floor observed.

155 Mb/s WDM label channel is detected directly by switch cells in a 4/spl times/4 optical crosspoint switch matrix without added optical components. Switching performance of 10 Gb/s packets is not affected by the detection process.