Modeling Electrical Switching of Nonvolatile Phase-Change Integrated Nanophotonic Structures with Graphene Heaters

ACS Applied Materials & Interfaces, Год журнала: 2020, Номер 12(19), С. 21827 - 21836

Опубликована: Апрель 16, 2020

Progress in integrated nanophotonics has enabled large-scale programmable photonic circuits (PICs) for general-purpose electronic-photonic systems on a chip. Relying the weak, volatile thermo-optic or electro-optic effects, such usually exhibit limited reconfigurability along with high energy consumption and large footprints. These challenges can be addressed by resorting to chalcogenide phase-change materials (PCMs) as Ge2Sb2Te5 (GST) that provide substantial optical contrast self-holding fashion upon phase transitions. However, current PCM-based applications are single devices simple PICs due poor scalability of electrical self-heating actuation approaches. Thermal-conduction heating via external heaters, instead, allows integration large-area switching, but fast energy-efficient control is yet show. Here, we model switching GST-clad nanophotonic structures graphene heaters based GST-on-silicon platform. Thanks ultra-low heat capacity in-plane thermal conductivity graphene, proposed speed ~80 MHz efficiency 19.2 aJ/nm^3 (6.6 aJ/nm^3) crystallization (amorphization) while achieving complete transitions ensure strong attenuation (~6.46 dB/micron) (~0.28 dB/micron at 1550 nm) modulation. Compared indium tin oxide silicon p-i-n display two orders magnitude higher figure merits overall performance. Our work facilitates analysis understanding thermal-conduction heating-enabled supports development future systems.

Язык: Английский

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Experimental investigation of silicon and silicon nitride platforms for phase-change photonic in-memory computing

Optica, Год журнала: 2020, Номер 7(3), С. 218 - 218

Опубликована: Янв. 22, 2020

Advances in artificial intelligence have greatly increased demand for data-intensive computing. Integrated photonics is a promising approach to meet this big-data processing due its potential wide bandwidth, high speed, low latency, and low-energy Photonic computing using phase-change materials combines the benefits of integrated co-located data storage, which late has evolved rapidly as an emerging area interest. In spite rapid advances demonstrations field on both silicon nitride platforms, clear pathway towards choosing between two been lacking. paper, we systematically evaluate compare computation performance platform platform. Our experimental results show that while platforms are superior terms integration, modulation device footprint, they require trade-offs energy efficiency. We then successfully demonstrate single-pulse optical memory photonic waveguides efficient programming, retention, readout > 4 bits per cell. paves way in-memory

Язык: Английский

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Silicon photonic microelectromechanical phase shifters for scalable programmable photonics

Optics Letters, Год журнала: 2021, Номер 46(22), С. 5671 - 5671

Опубликована: Окт. 19, 2021

Programmable photonic integrated circuits are emerging as an attractive platform for applications such quantum information processing and artificial neural networks. However, current programmable limited in scalability by the lack of low-power low-loss phase shifters commercial foundries. Here, we demonstrate a compact shifter with microelectromechanical system (MEMS) actuation on silicon photonics foundry (IMEC's iSiPP50G). The device attains (2.9π±π) shift at 1550 nm, insertion loss (0.33-0.10+0.15)dB, Vπ (10.7-1.4+2.2)V, Lπ (17.2-4.3+8.8)µm. We also measured bandwidth f-3dB 1.03 MHz air. believe that our demonstration MEMS implemented compatible technology lifts main roadblock toward scale-up circuits.

Язык: Английский

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Broadband Nonvolatile Electrically Controlled Programmable Units in Silicon Photonics

ACS Photonics, Год журнала: 2022, Номер 9(6), С. 2142 - 2150

Опубликована: Май 6, 2022

Programmable photonic integrated circuits (PICs) have recently gained significant interest because of their potential in creating next-generation technologies ranging from artificial neural networks and microwave photonics to quantum information processing. The fundamental building block such programmable PICs is a 2 × unit, traditionally controlled by the thermo-optic or free-carrier dispersion. However, these implementations are power-hungry volatile large footprint (typically >100 μm). Therefore, truly "set-and-forget"-type unit with zero static power consumption highly desirable for large-scale PICs. Here, we report broadband nonvolatile electrically silicon based on phase-change material Ge2Sb2Te5. directional coupler-type exhibits compact coupling length (64 μm), small insertion loss (∼2 dB), minimal crosstalk (<−8 dB) across entire telecommunication C-band while maintaining record-high endurance over 2800 switching cycles without performance degradation. This constitutes critical component realizing future generic systems.

Язык: Английский

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Prospects and Challenges of Photonic Switching in Data Centers and Computing Systems

Journal of Lightwave Technology, Год журнала: 2021, Номер 40(8), С. 2214 - 2243

Опубликована: Дек. 21, 2021

This Tutorial will discuss the motivation, benefits, and challenges of photonic switching in data centers cover prospects future involving emerging new technologies cross-layer solutions. The primary motivation for considering rises from need energy-efficient scalable intra-data center networks to meet rapid increases traffic driven by applications, including machine learning. inside (East-West traffic) is typically significantly greater than that coming out (North-South (Benson et al. 2010). To accommodate such traffic, today's large-scale employ cascaded stages many power-hungry electronic packet switches interconnected across network fixed hierarchical communication topologies. These add significant latency energy consumption while limiting bandwidth. On other hand, can, principle, support interconnections at very high rates on parallel wavelengths keeping their nearly independent switch port Numerous research papers have predicted benefits scalability, throughput, power efficiency deploying centers. However, not yet widely deployed commercial warehouse-scale time writing this due challenges. They are related 1) issues control management planes together with integrity during switching, 2) scalability >5000 racks (>a quarter-million servers), 3) performance monitoring required reliable operation, 4) currently existing standards allowing limited margin (3 dB), 5) practical (technology-dependent) relating polarization sensitivity, temperature cost, etc. In telecom, deployments reconfigurable optical add-drop multiplexers (ROADMs) (Lightwave, 2003)–(Perrin, 2015) also had faced similar took place ten years after first testbed demonstrations 1997 (Garrett, fully implemented planes. centers, far more scale dynamicity traffic. We possible solutions methods, topologies, innovative technologies. particular, broadly surveys state-of-the-art technologies, architectures, experimental results, further covers details arrayed-waveguide-grating-router-based fabrics offering hybrid methods distributed towards networking.

Язык: Английский

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Opportunities and Challenges for Large-Scale Phase-Change Material Integrated Electro-Photonics

ACS Photonics, Год журнала: 2022, Номер 9(10), С. 3181 - 3195

Опубликована: Сен. 29, 2022

Programmable photonics have the potential to completely transform a range of emerging applications, including optical computing, signal processing, light detecting and ranging, quantum applications. However, implementing energy-efficient large-scale systems remains elusive because commonly used programmable photonic approaches are volatile energy-hungry. Recent results on nonvolatile phase-change material (PCM) integrated present promising opportunity create truly photonics. The ability drastically change refractive index PCMs in fashion allows creating units with zero-static energy. By taking advantage electrical control, reconfiguration, zero crosstalk between each unit, can enable extra (ELSI) In this Perspective, we briefly review recent progress PCM discuss challenges limitations technology. We argue that energy efficiency is more critical parameter than operating speed for photonics, making an ideal candidate. This has disruptive paradigm shift reconfigurable research philosophy, as slow but large modulation provide better solution ELSI fast power-hungry, small tuning methods. also highlight exciting opportunities leverage wide bandgap visible-wavelength such optogenetics, rewritable circuits (PICs) using nanosecond pulsed lasers. latter dramatically reduce fabrication cost PICs democratize PIC manufacturing process rapid prototyping.

Язык: Английский

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High-speed Si-Ge avalanche photodiodes

PhotoniX, Год журнала: 2022, Номер 3(1)

Опубликована: Март 25, 2022

Abstract High-speed optical interconnects of data centers and high performance computers (HPC) have become the rapid development direction in field communication owing to explosive growth market demand. Currently, interconnect systems are moving towards higher capacity integration. High-sensitivity receivers with avalanche photodiodes (APDs) paid more attention due capability enhance gain bandwidth. The impact ionization coefficient ratio is one crucial parameter for photodiode optimization, which significantly affects excess noise bandwidth product (GBP). silicon-germanium (Si-Ge) APDs promising thanks low silicon, simple structure, CMOS compatible process. Separate absorption charge multiplication (SACM) structures typically adopted Si-Ge achieve noise. This paper reviews design optimization high-speed APDs, including advanced APD structures, modeling receivers.

Язык: Английский

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Scalability of Large-Scale Photonic Integrated Circuits

ACS Photonics, Год журнала: 2023, Номер 10(7), С. 2020 - 2030

Опубликована: Фев. 16, 2023

To keep up with the growing bandwidth demands, photonic integrated circuits (PICs) have been widely employed in various application scenarios where high capacity and high-bandwidth-density interconnects are required. However, it is challenging to scale PICs toward future petabit per second requirements. We study scalability bottlenecks of terms guiding materials, dense integration approaches, wide-band optical sources, high-efficiency tunable modulation devices. also look for possible solutions address these challenges. In end, we provide a perspective on PIC development. Moore's law photonics may last much shorter time than that microelectronics industry, requiring significant innovations technological breakthroughs research.

Язык: Английский

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Versatile parallel signal processing with a scalable silicon photonic chip

Nature Communications, Год журнала: 2025, Номер 16(1)

Опубликована: Янв. 2, 2025

Silicon photonic signal processors promise a new generation of processing hardware with significant advancements in bandwidth, low power consumption, and minimal latency. Programmable silicon processors, facilitated by tuning elements, can reduce development cycles costs. However, traditional programmable based on optical switches face scalability performance challenges due to control complexity transmission losses. Here, we propose scalable parallel processor for versatile applications interleaving wavelength temporal dimensions. Additionally, it incorporates ultra-low-loss waveguides low-phase-error switch techniques, achieving an overall insertion loss 10 dB. This design offers loss, high scalability, simplified control, enabling advanced functionalities such as accurate microwave reception, narrowband filtering, wide-bandwidth arbitrary waveform generation, high-speed computing without the need elements calibration. Our demonstrates advantages both scale performance, marking advancement large-scale, high-performance, multifunctional systems. work presents leveraging With switches, be programmed enable functions, showcasing great

Язык: Английский

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Implementation of on-chip multi-channel focusing wavelength demultiplexer with regularized digital metamaterials

Nanophotonics, Год журнала: 2019, Номер 9(1), С. 159 - 166

Опубликована: Ноя. 19, 2019

Abstract Adiabatic waveguide taper and on-chip wavelength demultiplexer are the key components of photonic integrated circuits. However, these two kinds devices which were designed by traditional semi-analytic methods or brute-force search usually have large size. Here, based on regularized digital metamaterials, a two-channel focused with footprint 2.4 × 10 μm 2 has been proposed. The can directly connect to grating coupler under absence long adiabatic taper. objective first method modified steepest descent used design splits 1520 nm 1580 light. Experimental results show that insertion loss upper (lower) channel is −1.77 dB (−2.10 dB) crosstalk −25.17 (−12.14 dB). Besides, simulation indicate fabrication tolerance device reach ±20 in etching depth ±10 plane size changing. Benefitted from extensibility method, other types ultra-compact “focused” devices, like mode splitters, converters, power splitters also be designed. Most importantly, this more complicated functionalities, such as multi-channel demultiplexers.

Язык: Английский

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