Figure 4.1: Improving VLSI testability using (a) demultiplexers; (b) multi-Abstract Asynchronous VLSI designs are becoming an intensive area of research due to their advantages in comparison with synchronous circuits, such as the absence of the clock distribution problem, lower power consumption and higher performance. The work described in this thesis is an attempt to find possible ways to tes...

Wavelength-division-multiplexing (WDM) technology has been developing in broadband optical networks. The wavelength range used in fiber transmission systems has been increasing by employing various kinds of fiber amplifiers. In order to make it possible to handle signals of multiple wavelengths efficiently in network nodes, wavelength-selective processing in switching, routing and buffering sys...

Optical wavelength division multiplexing (WDM) systems, with signals transmitted on different wavelengths through a single optical fiber, can have increased bandwidth and fault isolation properties over single wavelength optical systems. This paper considers two WDMsystem designs that might be used with multimode fibers and gives a general descripton of the components which could be used to imp...

We demonstrate a 10-channel InP-based Arrayed-Waveguide Grating (dimensions = 5.0x6.0 mm) with a 20-GHz channel spacing. The excess loss of the AWG is 5.5-6.3 dB, and the crosstalk level is below -15 dB. Introduction Arrayed waveguide Gratings (AWGs) are one of the key components for wavelength division multiplexing (WDM) applications, and narrowchannel-spacing AWG multi/demultiplexers are indi...

In the past decade, ultrashort laser sources have had a decisive impact on material processing for photonic applications. Since the first demonstration of bulk photowriting of light guides, the control of the irradiation outcome and the machining of more complex devices have been ongoing challenges. However, the technique is usually restricted to the elemental association of an ultrashort sourc...

Integrated photonic devices are poised to play a key role in a wide variety of applications, ranging from optical interconnects1 and sensors2 to quantum computing3. However, only a small library of semi-analytically designed devices is currently known4. Here, we demonstrate the use of an inverse design method that explores the full design space of fabricable devices and allows us to design devi...

In this paper the experimental demonstration of a Silicon-on-Insulator Reflective Arrayed Waveguide Grating (R-AWG) is reported. The device employs one Sagnac loop mirror per arm in the array, built with a 1x2 input/outputs, 50:50 splitting ratio, Multimode Interference coupler, for total reflection. The spectral responses obtained are compared to those of regular AWGs fabricated in the same di...

We have designed and fabricated tunable gratings with period tunable to within fraction of a micrometer. We actuated the gratings by electrostatic and piezoelectric means, and demonstrated period changes of order 1nm. Introduction Optical MEMS devices have included micro-mirrors [1, 2], tunable gratings, tunable Fabry-Perot resonators, etc. For example, Silicon Light Machines has commercialized...

We present a new approach in realizing multicore fibre fan-in/fan-out (FIFO) device. Using simple image demagnification by two fibre optic collimators a compact FIFO device for 4-core multicore fibre is fabricated with low crosstalk. Introduction One of the key optical components for space division multiplexed (SDM) transmission systems [1-3] is an efficient and stable SDM multiplexer/demultipl...

We present dual-polarization QPSK link transmission performance below the FEC limit with simultaneous transmission of three OAM states carrying 14×10-GBd WDM channels using silica 2D-3D hybrid integrated devices for OAM state multiplexing/demultiplexing capacity of 1.68 Tb/s. OCIS codes: (060.1660) Coherent communications; (050.4865) Optical vortices; (060.4230) Multiplexing Currently, space-di...