Photonic switches are increasingly considered for insertion in high performance datacenter architectures to meet the growing demands of interconnection networks. We provide an overview photonic switching technologies and develop evaluation methodology assessing their potential impact on performance. begin with a review three categories optical switches, namely, free-space III-V integrated silicon switches. The state-of-the-art MEMS, LCOS, SOA, MZI MRR covered, together insights limitations...

A detailed analysis of fundamental tradeoffs between ring radius and coupling gap size is presented to draw realistic borders the possible design space for microring resonators (MRRs). The coefficient ring-waveguide structure estimated based on an integration nonuniform waveguide. Combined with supermode two coupled waveguides, this approach further expanded into a closed-form equation that describes strength. This permits evaluate how distance separating waveguide from resonator, radius,...

We propose a universal and analytic step-by-step method to calculate the optimal 90° 180° waveguide bends (L-bends U-bends) in silicon-on-insulator photonics platform. This approach consists of first building an model loss per unit length as function radius curvature then using variational optimization bending loss. It is shown that shape ultimately determined either by radiation tight if bend set eliminate mode-mismatch losses or sidewall roughness large. Numerical results from full wave...

Deep learning is revolutionizing many aspects of our society, addressing a wide variety decision-making tasks, from image classification to autonomous vehicle control. Matrix multiplication an essential and computationally intensive step deep-learning calculations. The computational complexity deep neural networks requires dedicated hardware accelerators for additional processing throughput improved energy efficiency in order enable scaling larger the upcoming applications. Silicon photonics...

The paper presents a comprehensive physical layer design and modeling platform for silicon photonic interconnects. is based on explicit closed-form expressions optical power penalties, derived both signal-dependent signal-independent noise contexts. Our models agree well with reported experimental measurements. We show how the approach used space exploration of links can be leveraged to optimize wavelength-division multiplexed (WDM) capacity, evaluate scalability, study sensitivity system...

Heating elements are used to tune the optical properties of silicon photonic devices, stabilize operating temperatures, and compensate for fabrication variations. In this paper, we characterize transient thermal response develop models devices equipped with such heating mechanisms. To demonstrate usefulness practicality proposed models, investigate pulse width modulation (PWM) drive scheme microheaters experimentally its use in stabilizing microring resonators by digital driving signals...

We propose and analyze a scalable microring-based Clos switch fabric architecture constructed with switch-and-select switching stages. A silicon 4 × building block that was designed fabricated through American Institute for Manufacturing Integrated Photonics is used the proof-of-principle demonstration of 16 fabric. By fully blocking first-order crosstalk, device measured to show crosstalk ratio in range -57 -48.5 dB, enabling better than -39 dB switch. Our study shows three-stage design...

The Dragonfly topology provides low-diameter connectivity for high-performance computing with all-to-all global links at the inter-group level. Our traffic matrix characterization of various scientific applications shows consistent mismatch between imbalanced group-to-group and uniform bandwidth allocation Dragonfly. Though adaptive routing has been proposed to utilize non-minimal paths, increased hops cross-group interference lower efficiency. This work presents a photonic architecture,...

We examine inter-channel and intra-channel crosstalk power penalties between non-return-to-zero on-off keying (NRZ-OOK) wavelength-division-multiplexing (WDM) channels for microring-based silicon photonic interconnects. first propose a new model that relates the penalty to interfering signals power, extinction ratio of non-return-to-zero, OOK modulated "victim" channel, finally bit-error-ratio is referenced to. As crosstalk, proposed agrees well with our recent experimental measurements....

We present the design, modeling, fabrication, and characterization of grating coupler devices for z-cut lithium niobate near 1550 nm. first experimentally measure sensitivity insertion loss a conventional to translational misalignment through three-factor full factorial design experiment. Next, we couplers that are significantly less sensitive misalignment. The fabricated experienced than 7 dB excess combined misalignments up ± 5 μm in plane -2 or + 10 out plane.

We present detailed electrical and optical models of the elements that comprise a WDM silicon photonic link. The electronics is assumed to be based on 65 nm CMOS node modulators demultiplexers are microring resonators. goal this study analyze energy consumption scalability link by finding right combination (number channels × data rate per channel) fully covers available power budget. Based set empirical analytical presented in work, maximum capacity 0.75 Tbps can envisioned for...

The large electro-optic coefficient, r 33 , of thin-film lithium niobate (LN) on insulator makes it an excellent material platform for high-efficiency optical modulators. Using the fundamental transverse magnetic mode in Z-cut LN enables isotropic in-plane devices; however, realizing a strong vertical electric field to capitalize has been challenging. Here we present symmetric electrode configuration boost strength inside fully-etched single-mode waveguide. We use this design paradigm...

We investigate the impact of waveguide curvature on electro-optic efficiency microring resonators in thin-film X-cut or Y-cut lithium niobate (in-plane extraordinary axis) and derive explicit relations response. It is shown that such modulators have a fundamental upper bound their performance (∼50% filling factor) which corresponds to specific arrangement metal electrodes surrounding yields nearly identical results for designs. further show this limitation does not exist (i.e., 100% factor...

The Dragonfly topology provides low-diameter connectivity for high-performanceleb computing with all-to-all global links at the inter-group level. Our traffic matrix characterization of various scientific applications shows consistent mismatch between imbalanced group-to-group and uniform bandwidth allocation Dragonfly. Though adaptive routing has been proposed to utilize non-minimal paths, increased hops cross-group interference lower efficiency. This work presents a photonic architecture,...

Disaggregation enabled by silicon photonic switch fabrics is a path to low-cost and energy-efficient data centers. The routing strategy, which can be seamlessly incorporated into the control plane, potentially provides an additional dimension for physical-layer performance optimization, at no extra cost. In this paper, we analyze role of optical strategies fabrics. We define quantify number global switching states in various topologies discuss their relationship permutations. propose...

We demonstrate a programmable control-plane based on field gate array (FPGA) with power-efficient algorithm for optical unicast, multicast, and broadcast functionalities in silicon photonic platform. The platform includes 1×8 microring chip which conjunction fast tunable laser over the C-band is capable of delivering software controlled wavelength selective functionality top spatial switching. characterize thermo-optic response resonators extract key parameters necessary development...

A simple yet accurate model for the analysis of coupling between arrayed plasmonic slot cavities and bus/drop metal-dielectric-metal waveguides is presented. The evanescent region replaced by a transmission line section whose propagation constant characteristic impedance are given in closed form. side bus waveguide cavity modeled together with direct drop channel. proposed validated using rigorous numerical method, used to design typical demultiplexer.

Exploration of energy-bandwidth tradeoffs is performed for a silicon photonic link, showing maximum capacity 1.9 Tb/s with an energy cost 1.54 pJ/bit at 13 Gb/s signaling rate. We conclude that 10 yields good trade-off between throughput and efficiency.

The article describes an experimentally validated approach for optimizing wavelength-selective microring filters based on optical signals power penalties. methodology is used to analyze the performance of WDM links various bit rates and channel-spacing.

We present our design, fabrication, and experimental results for very highperformance isotropic microring resonators with small radii (~ 30 μm) based on single-mode strip waveguides transverse magnetic (TM) polarization in a fully etched lithium niobate (Z-cut) thin-film insulator.The loss of the devices is predicted to be < 10 dB/cm, measured ~ 7 dB/cm.The optical responses exhibit an extinction 25 dB (close critical coupling), 3 bandwidth 49 pm 6 GHz) all-pass structures, add-drop free...

Smart routing tables aware of physical-layer parameters are first realized for a 4×4-port silicon switch device, improving the worst-case power-penalty by 8.8dB and reducing dynamic-range requirement on receivers 7.8dB. An 8×8-port is further simulated achieving 16.1dB power penalty improvement.

We leverage the photo-conductance (PC) effect in doped phase-shifter heaters for both controlling and calibrating Mach-Zehnder interferometer (MZI) switch elements. Both steady-state transient response are experimentally characterized, compact models PC current developed. Utilizing effect, a topology-agnostic algorithm is then outlined. The calibration procedure verified against with external photo-detectors using non-blocking 4×4 Benes consisting of six 2×2 MZIs. It shown that our PC-based...

A circuit model based on the transmission line theory is proposed to analyze recently introduced metal-insulator-metal (MIM) complementary split-ring resonators (CSRRs). It shown that integer and noninteger modes of CSRRs can be characterized by models with short- open-circuited terminals. The then extended incorporate side-coupling effects between straight MIM waveguides. Thereby, simple closed-form expressions are provided for coupling quality factor. waveguide resonator structures at...