A5046772540- Photonic and Optical Devices
- Optical Network Technologies
- Advanced Photonic Communication Systems
- Semiconductor Lasers and Optical Devices
- Radio Frequency Integrated Circuit Design
- Advancements in PLL and VCO Technologies
- Advanced Optical Sensing Technologies
- Semiconductor Quantum Structures and Devices
- Analog and Mixed-Signal Circuit Design
- Neural Networks and Reservoir Computing
- Semiconductor materials and devices
- Advanced Fiber Laser Technologies
- Ocular and Laser Science Research
- Photonic Crystals and Applications
- VLSI and Analog Circuit Testing
- Advanced Fluorescence Microscopy Techniques
- Semiconductor materials and interfaces
- Integrated Circuits and Semiconductor Failure Analysis
- Silicon Nanostructures and Photoluminescence
Texas A&M University
2015-2019
Analog Devices (United States)
2015-2018
Hewlett Packard Enterprise (United States)
2018
Hewlett-Packard (United States)
2015-2016
Tsinghua University
2012-2014
Institute of Microelectronics
2012
University of California, San Diego
2002
Silicon-germanium (Si–Ge)-based avalanche photodiodes (APDs) have shown a significant improvement in receiver sensitivity compared to their III–V counterparts due the superior impact ionization property of silicon. However, conventional Si–Ge APDs typically operate at high voltages and low speed, limiting application this technology data communication. In paper, we present waveguide photodiode using thin silicon multiplication region with breakdown voltage −10 V, speed 25 GHz,...
Silicon photonics devices offer promising solution to meet the growing bandwidth demands of next-generation interconnects. This paper presents a 5 × 25 Gb/s carrier-depletion microring-based wavelength-division multiplexing (WDM) transmitter in 65 nm CMOS. An AC-coupled differential driver is proposed realize 4 VDD output swing as well tunable DC-biasing. The incorporates 2-tap asymmetric pre-emphasis effectively cancel optical nonlinearity ring modulator. average-power-based dynamic...
Single-mode wavelength-division multiplexing (WDM) optical links are an attractive technology to meet the growing interconnect bandwidth demand in data center applications. This paper presents a multi-channel hybrid-integrated photonic receiver based on microring drop filters and waveguide photodetectors implemented 130 nm SOI process high-speed front-ends designed 65 CMOS. The source-synchronous utilizes LC injection-locked oscillator (ILO) clock path for improved jitter filtering, while...
Optical interconnect system efficiency is dependent on the ability to optimize transceiver circuitry for low-power and high-bandwidth operation, motivating co-simulation environments with compact optical device simulation models. This paper presents a Verilog-A silicon carrier-injection ring modulator model, which accurately captures both non-linear electrical dynamics. The device's behavior described by p-i-n diode SPICE while response captured dynamic resonator considers ring's cumulative...
Utilizing four-level pulse-amplitude modulation (PAM-4) with vertical-cavity surface emitting lasers (VCSELs) is challenging due to device nonlinearity and bandwidth limitations. This letter presents a VCSEL-based PAM-4 transmitter that employs 2.5-tap nonlinear equalizer compensate for these issues. The utilizes lookup-table control of current-mode digital-to-analog converter (DAC) output stage enable independent equalization coefficients different symbol transitions. half pre-cursor (MSB...
Wavelength-division multiplexing (WDM) optical interconnect architectures based on microring resonator devices offer a low-area and energy-efficient approach to realize both high-speed modulation WDM with transmit-side ring modulators high-Q receive-side drop filters [1-3]. While CMOS front-ends have been previously developed that support data-rates in excess of 20Gb/s, these designs often do not the retiming deserialization functions required form complete link [1,4]. Furthermore, along...
Silicon photonic interconnects have the potential to break bandwidth-distance limitations intrinsically associated with electrical links. This paper presents a dual-mode NRZ/PAM4 silicon transmitter based on segmented-electrode Mach-Zehnder Modulator (SE-MZM). The portion of transmitter, fabricated in 16nm FinFET process, utilizes stacked-CMOS push-pull driver stages that include parallel asymmetric fast discharging path compensate for slow transition edge caused by nonlinear capacitance...
A silicon photonic microring resonator modulator transmitter utilizes a segmented pulsed-cascode output stage for voltage level control to achieve PAM4 modulation on single device. The 65nm CMOS achieves 40Gb/s operation at 3.04mW/Gb/s when driving depletion-mode modulators with 4.4Vppd swing.
A two-segment silicon photonic microring modulator implements an optical DAC for PAM4 modulation. Independent level and edge-rate control is achieved using segmented MSB/LSB pulsed-cascode drivers. The 65nm CMOS transmitter achieves 40Gb/s operation at 4.38mW/Gb/s while driving each segment with 4.4V <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">ppd</sub> swing.
Silicon photonic microring modulators (MRMs) offer a promising approach for realizing energy-efficient wavelength-division multiplexing (WDM) optical interconnects. For data-rates greater than 10Gb/s, depletion-mode MRMs are generally preferred over their injection-mode counterparts due to shorter carrier lifetimes and resulting higher bandwidths. Unfortunately, these typically exhibit low PN junction tunability, thereby requiring modulation voltages in order provide >6dB extinction ratios...
Optical connectivity, which has been widely deployed in today's datacenters and high-performance computing (HPC) systems, is a disruptive technological revolution to the IT industry new Millennium.In our journey debut an Exascale supercomputer, completely concept, called memorydriven computing, was innovated recently.This architecture brings challenges opportunities for novel optical interconnect solutions.Here, we first discuss strategy develop appropriate link solutions different data...
A 25Gb/s hybrid-integrated microring receiver which includes a thermal tuning loop that stabilizes the drop filter resonance wavelength is implemented. The multi-channel 65nm CMOS source-synchronous achieves −8.2 dBm sensitivity at BER<10−12 and 0.68pJ/b.
Advanced modulation schemes, such as PAM4, are currently under consideration in both high-speed electrical and optical interconnect systems. This paper analyzes how NRZ PAM4 impacts the energy efficiency of an link architecture based on silicon photonic microring resonator modulators drop filters, this changes CMOS technology scales from a 65nm to 16nm node. Two ring modulator device structures proposed for modulation, including single-segment driven with multi-level transmitter two-segment...
Increased data rates have motivated the investigation of advanced modulation schemes, such as four-level pulseamplitude (PAM4), in optical interconnect systems order to enable longer transmission distances and operation with reduced circuit bandwidth relative non-return-to-zero (NRZ) modulation. Employing this scheme architectures based on high-Q silicon photonic microring resonator devices, which occupy small area allow for inherent wavelength-division multiplexing (WDM), offers a promising...
We present energy-efficient microring resonator-based silicon photonic transceivers for DWDM optical interconnect.
This paper presents a 56Gb/s PAM-4 optical receiver analog frontend circuits which consists of three inverter stages TIA with resistive feedback in the first and third stages. An adaptively-tuned continuous-time linear equalizer (CTLE) is cascaded after for improved sensitivity bandwidth. The overall gain controlled by an automatic control (AGC) to avoid large input power saturates TIA, thus distorting signals. designed advanced FinFET technology achieves 68 dBO 22 GHz simulated referred...
This paper examines the potential of silicon photonic microring resonator-based optical transceivers for compact wavelength-division multiplexing (WDM) interconnects. An overview devices typically found in a ring resonator interconnect platform is provided and design transceiver circuits which address key challenges related to modulators drop filters described. The possibility further improvements bandwidth density via efficient implementations >50Gb/s PAM4 modulation with detailed.
Future RF photonic systems offer the promise of wideband front-end operation, but are limited by linearity in electrical-to-optical conversion process. This paper presents a fifth-order polynomial predistortion circuit for optical Mach-Zehnder modulator linearization. Inclusion independently tunable coefficients provides flexibility to suppress both third-order (IM3) and (IM5) intermodulation products. Fabricated 65nm CMOS, achieves measured IM3 suppression 19.5dB 17.1dB with modulation...
In this paper, a novel clock and data recovery scheme for 10Gbps source synchronous receiver is presented in 65nm CMOS technology, which includes the implementation of quadrature generation circuit CDR circuit. The based on an open loop delay line, avoiding design complex DLL or PLL often used links. phase interpolator, algorithm proposed to reduce jitter recovered clock. power consumption 25mW under 1.2V supply.
We investigate the effects of guard-ring structure on noise characteristics for CMOS-compatible single-photon avalanche diodes (SPADs). SPADs with different structures are fabricated in standard 0.18-μm CMOS technology and as dark current, dark-count rate afterpulsing probability measured analyzed.
An accurate methodology for analyzing the Mach-Zehnder modulator (MZM) based optical link power budget is presented. It optimizes transceiver's system-level performance to meet specifications of links with N-level (N=2,4,8) pulse amplitude modulation format high-speed signaling.
A multi-wavelength, hybrid directly-modulated laser (DML) transmitter with integrated thermal shunt, MOS capacitor and CMOS driver circuit is fabricated. 14 Gb/s operation from conventional direct current modulation a novel MOS-type are demonstrated.
We have demonstrated a high-performance InGaAs-on-silicon APD that exhibits very low dark current density of 0.7 mA/cm/sup 2/, high avalanche gain (M/spl Gt/100), an RC-limited bandwidth 1.45 GHz, and gain-bandwidth product 290 GHz. estimate our device can achieve sensitivity improvement 5 dB compared to state-of-the-art InP-based receivers. are currently measuring the excess noise factor. will report this measurement at conference.
A Verilog-A carrier-injection ring modulator model accurately captures electrical and optical dynamics. The impact of pre-emphasis pulse duration, depth, DC bias is demonstrated with excellent matching between simulated measured 8Gb/s eye diagrams.
The first demonstration of a hybrid-integrated directly modulated microring laser transmitter operating up to 14 Gb/s operation is reported. A CMOS driver with an asymmetric 2-tap feed-forward compensates for the non-linear dynamics.