Mj Michael Wale

Widely tunable DS-DBR laser with monolithically integrated SOA: design and performance

We report recent device characterization results for a fully packaged widely tunable digital supermode (DS) distributed Bragg reflector (DBR) laser which has been monolithically integrated with a semiconductor optical amplifier. This new device gives all of the wide tunability and high side-mode suppression ratio performance previously reported for the DS-DBR laser with the added feature of output powers in excess of 14 dBm in fiber. In addition to output power and basic tuning behavior, we report on linewidth and relative intensity noise measurements for this device in order to investigate the noise characteristics of this laser.

An introduction to InP-based generic integration technology

Photonic integrated circuits (PICs) are considered as the way to make photonic systems or subsystems cheap and ubiquitous. PICs still are several orders of magnitude more expensive than their microelectronic counterparts, which has restricted their application to a few niche markets. Recently, a novel approach in photonic integration is emerging which will reduce the R&D and prototyping costs and the throughput time of PICs by more than an order of magnitude. It will bring the application of PICs that integrate complex and advanced photonic functionality on a single chip within reach for a large number of small and larger companies and initiate a breakthrough in the application of Photonic ICs. The paper explains the concept of generic photonic integration technology using the technology developed by the COBRA research institute of TU Eindhoven as an example, and it describes the current status and prospects of generic InP-based integration technology.

10 Gb/s optical differential quadrature phase shift key (DQPSK) transmission using GaAs/AlGaAs integration

We demonstrate the first integrated realization of a new modulation format-optical DQPSK. Transmission experiments using an integrated encoder demonstrate tolerance to chromatic dispersion, polarization mode dispersion, self phase modulation and low OSNR.

Packaged semiconductor laser optical phase-locked loop (OPLL) for photonic generation, processing and transmission of microwave signals

In this paper, we present the first fully packaged semiconductor laser optical phase-locked loop (OPLL) microwave photonic transmitter. The transmitter is based on semiconductor lasers that are directly phase locked without the use of any other phase noise-reduction mechanisms. In this transmitter, the lasers have a free-running summed linewidth of 6 MHz and the OPLL has a feedback bandwidth of 70 MHz. A state-of-the-art performance is obtained, with a total phase-error variance of 0.05 rad/sup 2/ (1-GHz bandwidth) and a carrier phase-error variance of 7/spl times/10/sup -4/ rad/sup 2/ in a 15-MHz bandwidth. Carriers are generated in the range of 7-14 GHz. The OPLL transmitter has been fully packaged for practical use in field trials. This is the first time this type of transmitter has been fabricated in a packaged state which is a significant advance on the route to practical application.

InP-Based Photonic Multiwavelength Transmitter With DBR Laser Array

We demonstrate an InP-based photonic multiwavelength transmitter realized by integrating an array of distributed Bragg reflector lasers with modulators in Mach-Zehnder configuration. An arrayed waveguide grating is used to multiplex the generated signals into a common optical output. The device is designed according to a generic integration concept, using standardized building blocks, and is fabricated in a multiproject wafer run. The device delivers up to 4 dBm of optical power into the fiber with a modulation data rate of 12.5 Gbps per transmission channel. The obtained performance makes it very promising for application in the next generation optical access networks as a key source in the central office part of the telecommunication systems.

Integrated DQPSK transmitter for dispersion-tolerant and dispersion-managed DWDM transmission

We demonstrate GaAs integration of an encoder for optical DQPSK transmission. Experiments demonstrate application to dispersion-tolerant 10 Gb/s transmission over an uncompensated fiber span up to 250 km, and high spectral efficiency 20 Gb/s transport.

Quasi-static analysis of electrooptic modulators by the method of lines

A quasi-TEM analysis using the method of lines is implemented to calculate the electric field anywhere within a layered guided wave structure at appropriately low frequencies. The analysis provides the electric fields and transmission-line parameters for a shielded structure having any number of coplanar electrodes within an arbitrary number of anisotropic dielectric layers, the principal axes of which are parallel to the axes of the structure. The practical application considered is the calculation of the phase shift of a guided optical wave within an electrooptic modulator that has a dielectric buffer layer between the electrodes and electrooptic substrate. >

InP-Based Integrated Optical Pulse Shaper: Demonstration of Chirp Compensation

We demonstrate dispersion compensation for highly chirped optical pulses with an ultracompact optical pulse shaper. The device integrates a 20-channel arrayed waveguide grating with 20 phase modulators and 20 semiconductor optical amplifiers on a single chip of 6 × 6 mm2. The chip has been realized in an InP-based generic photonic foundry process, which enables a significant reduction in design effort using standardized building blocks.

A generic foundry model for InP-based photonic ICs

Europe is making significant investments in development of generic photonic foundry platform infrastructures for InP-based and Silicon Photonic ICs. Here we present the present status for the InP-based JePPIX platform.

Advanced Integration Techniques on Broadband Millimeter-Wave Beam Steering for 5G Wireless Networks and Beyond

Recently, the desired very high throughput of 5G wireless networks drives millimeter-wave (mm-wave) communication into practical applications. A phased array technique is required to increase the effective antenna aperture at mm-wave frequency. Integrated solutions of beamforming/beam steering are extremely attractive for practical implementations. After a discussion on the basic principles of radio beam steering, we review and explore the recent advanced integration techniques of silicon-based electronic integrated circuits (EICs), photonic integrated circuits (PICs), and antenna-on-chip (AoC). For EIC, the latest advanced designs of on-chip true time delay (TTD) are explored. Even with such advances, the fundamental loss of a silicon-based EIC still exists, which can be solved by advanced PIC solutions with ultra-broad bandwidth and low loss. Advanced PIC designs for mm-wave beam steering are then reviewed with emphasis on an optical TTD. Different from the mature silicon-based EIC, the photonic integration technology for PIC is still under development. In this paper, we review and explore the potential photonic integration platforms and discuss how a monolithic integration based on photonic membranes fits the photonic mm-wave beam steering application, especially for the ease of EIC and PIC integration on a single chip. To combine EIC, for its accurate and mature fabrication techniques, with PIC, for its ultra-broad bandwidth and low loss, a hierarchical mm-wave beam steering chip with large-array delays realized in PIC and sub-array delays realized in EIC can be a future-proof solution. Moreover, the antenna units can be further integrated on such a chip using AoC techniques. Among the mentioned techniques, the integration trends on device and system levels are discussed extensively.