Scalability of Optical Interconnects Based on Microring Resonators

This letter investigates the use of optical microring resonators as switching elements (SEs) in large optical interconnection fabrics. We introduce a simple physical-layer model to assess scalability in crossbar- and Benes-based architectures.We also propose a new dilated SE that improves scalability to build fabrics of several terabits per second of aggregate capacit

Vertical liquid controlled adiabatic waveguide coupler

A broadband vertical liquid controlled optical waveguide coupler (LCC) is demonstrated. The fabricated vertical LCC with silicon nitride (SiN) waveguides can switch light between 2 stacked photonic circuit layers with zero energy consumption in a steady switch state. In combination with low-loss interlayer waveguide crossovers they enable large scale non-volatile switch circuits with low loss. The fabricated vertical LCC has a loss less than 2.0 dB in bar state and less than 2.6 dB in cross state over the telecommunication wavelength range 1260 nm to 1630 nm. Interlayer waveguide crossovers with the same interlayer oxide thickness as the LCC have a loss less than 0.06 dB over the same wavelength range. The crosstalk of the LCC is less than 21 dB over the wavelength range 1500 nm to 1630 nm for both bar and cross state. (c) 2018 Optical Society of America under the terms of the OSA Open Access Publishing Agreemen

Demonstration of the feasibility of large-port-count optical switching using a hybrid Mach-Zehnder interferometer-semiconductor optical amplifier switch module in a recirculating loop.

For what we believe is the first time, the feasibility of large-port-count nanosecond-reconfiguration-time optical switches is demonstrated using a hybrid approach, where Mach-Zehnder interferometric (MZI) switches provide low-loss, high-speed routing with short semiconductor optical amplifiers (SOAs) being integrated to enhance extinction. By repeatedly passing signals through a monolithic hybrid dilated 2×2 switch module in a recirculating loop, the potential performance of high-port-count switches using the hybrid approach is demonstrated. Experimentally, a single pass switch penalty of only 0.1 dB is demonstrated for the 2×2 module, while even after seven passes through the switch, equivalent to a 128×128 router, a penalty of only 2.4 dB is recorded at a data rate of 10 Gb/s.This is the author accepted manuscript. The final version is published in Optics Letters - http://www.opticsinfobase.org/ol/abstract.cfm?uri=ol-39-18-5244

The feasibility of building large scale optical switches using a novel MZI-SOA hybrid approach

For the first time, the feasibility of nanosecond large-scale optical switches is demonstrated using a novel MZI-SOA hybrid approach. In a filter-free recirculating loop, the potential performance of up to 128x128 port switch is demonstrated.This is the author accepted manuscript. The final version is available from OSA Publishing via http://dx.doi.org/10.1364/ACPC.2014.AF2B.

Robust large-port-count hybrid switches with relaxed control tolerances

The control tolerances of large-port-count optical switches with up to 128×128 ports using the MZI-SOA hybrid design are investigated. The first quantitative analysis is presented showing tolerant control requirements of the hybrid switch design.The research leading to these results has received funding from the UK EPSRC INTERNET, STAR, and COPOS II projects and the European Community’s FP7 programme under grant agreement ICT 257210 PARADIGM.This is the accepted manuscript. The final version is available at https://www.osapublishing.org/abstract.cfm?uri=CLEO_SI-2015-JTh2A.38

Reducing Crosstalk of Silicon-based Optical Switch with All-optical Multi-wavelength Regenerator

Improving crosstalk performance of Mach–Zehnder-interferometer-type optical switches is experimentally investigated by use of an all-optical multi-wavelength regenerator. Extinction ratio and bit error rate of WDM signals are simultaneously improved in proposed regenerative optical switching

Switching to Photonics

The use of hardware that exploits the interplay of photons and electrons to switch voice, data, and video is discussed. The two directions being taken by current research-guided-wave and free-space photonics-are examined. Photonic time-slot interchanges are described. Multidivisional fabrics, based on a combination of space-division and time-division multiplexing, are considered, as is the wavelength-division-based photonic packet switch, another kind of multidimensional fabric. The use of self-electrooptic effect devices, (SEEDs) is discussed

Designing a multi-hop regular virtual topology for ultrafast optical packet switching : node placement optimisation and/or dilation minimisation?

This paper studies the design of multi-hop regular virtual topologies to facilitate optical packet switching in networks with arbitrary physical topologies. The inputs to the virtual topology design problem are the physical topology, the traffic matrix and the regular topology. In this paper, this problem is tackled directly and also by decomposition into two sub-problems. The first sub-problem, dilation minimisation, uses only the physical topology and the virtual topology as optimisation inputs. The second sub-problem considers the traffic matrix and virtual topology as optimisation inputs. The solutions of these two sub-problems are compared with each other and against the results obtained when the global problem is optimised (using all three possible input parameters) for a variety of traffic scenarios. This gives insight into the key question of whether the physical topology or the traffic matrix is the more important parameter when designing a regular virtual topology for optical packet switching. Regardless of the approach taken the problem is intractable and hence heuristics must be used to find (near) optimal solutions in reasonable time. Five different optimisation heuristics, using different artificial intelligence techniques, are employed in this paper. The results obtained by the heuristics for the three alternative design approaches are compared under a variety of traffic scenarios. An important conclusion of this paper is that the traffic matrix plays a less significant role than is conventionally assumed, and only a marginal penalty is incurred by disregarding it in several of the traffic cases considered