1
|
Wu Q, Qian J, Wang Y, Xing L, Wei Z, Gao X, Li Y, Liu Z, Liu H, Shu H, Yin J, Wang X, Peng H. Waveguide-integrated twisted bilayer graphene photodetectors. Nat Commun 2024; 15:3688. [PMID: 38693107 PMCID: PMC11063206 DOI: 10.1038/s41467-024-47925-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/17/2024] [Accepted: 04/16/2024] [Indexed: 05/03/2024] Open
Abstract
Graphene photodetectors have exhibited high bandwidth and capability of being integrated with silicon photonics (SiPh), holding promise for future optical communication devices. However, they usually suffer from a low photoresponsivity due to weak optical absorption. In this work, we have implemented SiPh-integrated twisted bilayer graphene (tBLG) detectors and reported a responsivity of 0.65 A W-1 for telecom wavelength 1,550 nm. The high responsivity enables a 3-dB bandwidth of >65 GHz and a high data stream rate of 50 Gbit s-1. Such high responsivity is attributed to the enhanced optical absorption, which is facilitated by van Hove singularities in the band structure of high-mobility tBLG with 4.1o twist angle. The uniform performance of the fabricated photodetector arrays demonstrates a fascinating prospect of large-area tBLG as a material candidate for heterogeneous integration with SiPh.
Collapse
Affiliation(s)
- Qinci Wu
- Center for Nanochemistry, Beijing Science and Engineering Center for Nanocarbons, Beijing National Laboratory for Molecular Sciences, College of Chemistry and Molecular Engineering, Peking University, 100871, Beijing, P. R. China
- Beijing Graphene Institute, 100095, Beijing, P. R. China
| | - Jun Qian
- Center for Nanochemistry, Beijing Science and Engineering Center for Nanocarbons, Beijing National Laboratory for Molecular Sciences, College of Chemistry and Molecular Engineering, Peking University, 100871, Beijing, P. R. China
- Beijing Graphene Institute, 100095, Beijing, P. R. China
| | - Yuechen Wang
- Center for Nanochemistry, Beijing Science and Engineering Center for Nanocarbons, Beijing National Laboratory for Molecular Sciences, College of Chemistry and Molecular Engineering, Peking University, 100871, Beijing, P. R. China
- Beijing Graphene Institute, 100095, Beijing, P. R. China
- Academy for Advanced Interdisciplinary Studies, Peking University, 100871, Beijing, P. R. China
| | - Luwen Xing
- State Key Laboratory of Advanced Optical Communications System and Networks, School of Electronics, Peking University, 100871, Beijing, P. R. China
- School of Engineering, Peking University, 100871, Beijing, P. R. China
| | - Ziyi Wei
- State Key Laboratory of Advanced Optical Communications System and Networks, School of Electronics, Peking University, 100871, Beijing, P. R. China
| | - Xin Gao
- Center for Nanochemistry, Beijing Science and Engineering Center for Nanocarbons, Beijing National Laboratory for Molecular Sciences, College of Chemistry and Molecular Engineering, Peking University, 100871, Beijing, P. R. China
- Beijing Graphene Institute, 100095, Beijing, P. R. China
- Academy for Advanced Interdisciplinary Studies, Peking University, 100871, Beijing, P. R. China
| | - Yurui Li
- Beijing Graphene Institute, 100095, Beijing, P. R. China
- Academy for Advanced Interdisciplinary Studies, Peking University, 100871, Beijing, P. R. China
| | - Zhongfan Liu
- Center for Nanochemistry, Beijing Science and Engineering Center for Nanocarbons, Beijing National Laboratory for Molecular Sciences, College of Chemistry and Molecular Engineering, Peking University, 100871, Beijing, P. R. China
- Beijing Graphene Institute, 100095, Beijing, P. R. China
- Academy for Advanced Interdisciplinary Studies, Peking University, 100871, Beijing, P. R. China
| | - Hongtao Liu
- Center for Nanochemistry, Beijing Science and Engineering Center for Nanocarbons, Beijing National Laboratory for Molecular Sciences, College of Chemistry and Molecular Engineering, Peking University, 100871, Beijing, P. R. China
| | - Haowen Shu
- State Key Laboratory of Advanced Optical Communications System and Networks, School of Electronics, Peking University, 100871, Beijing, P. R. China
| | - Jianbo Yin
- Beijing Graphene Institute, 100095, Beijing, P. R. China.
- Academy for Advanced Interdisciplinary Studies, Peking University, 100871, Beijing, P. R. China.
- State Key Laboratory of Advanced Optical Communications System and Networks, School of Electronics, Peking University, 100871, Beijing, P. R. China.
| | - Xingjun Wang
- State Key Laboratory of Advanced Optical Communications System and Networks, School of Electronics, Peking University, 100871, Beijing, P. R. China.
| | - Hailin Peng
- Center for Nanochemistry, Beijing Science and Engineering Center for Nanocarbons, Beijing National Laboratory for Molecular Sciences, College of Chemistry and Molecular Engineering, Peking University, 100871, Beijing, P. R. China.
- Beijing Graphene Institute, 100095, Beijing, P. R. China.
- Academy for Advanced Interdisciplinary Studies, Peking University, 100871, Beijing, P. R. China.
| |
Collapse
|
2
|
Xue Y, Zhang L, Ren Y, Lei Y, Sun X. Fast Adiabatic Mode Evolution Assisted 2 × 2 Broadband 3 dB Coupler Using Silicon-on-Insulator Fishbone-like Grating Waveguides. NANOMATERIALS (BASEL, SWITZERLAND) 2023; 13:2776. [PMID: 37887927 PMCID: PMC10609444 DOI: 10.3390/nano13202776] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/16/2023] [Revised: 10/11/2023] [Accepted: 10/13/2023] [Indexed: 10/28/2023]
Abstract
We report a novel 2 × 2 broadband 3 dB coupler based on fast adiabatic mode evolution with a compact footprint and large bandwidth. The working principle of the coupler is based on the rapid adiabatic evolution of local eigenmodes of fishbone-like grating waveguides. Different from a traditional adiabatic coupling method realized by the slow change of the cross-section size of a strip waveguide, a fishbone waveguide allows faster adiabatic transition with proper structure and segment designs. The presented 3 dB coupler achieves a bandwidth range of 168 nm with an imbalance of no greater than ±0.1 dB only for a 9 μm coupling region which significantly improves existing adiabatic broadband couplers.
Collapse
Affiliation(s)
- Yulong Xue
- State Key Laboratory of Transient Optics and Photonics, Xi’an Institute of Optics and Precision Mechanics, Chinese Academy of Sciences, Xi’an 710119, China; (L.Z.); (Y.R.); (Y.L.)
- University of Chinese Academy of Sciences, Beijing 100049, China
| | - Lingxuan Zhang
- State Key Laboratory of Transient Optics and Photonics, Xi’an Institute of Optics and Precision Mechanics, Chinese Academy of Sciences, Xi’an 710119, China; (L.Z.); (Y.R.); (Y.L.)
| | - Yangming Ren
- State Key Laboratory of Transient Optics and Photonics, Xi’an Institute of Optics and Precision Mechanics, Chinese Academy of Sciences, Xi’an 710119, China; (L.Z.); (Y.R.); (Y.L.)
| | - Yufang Lei
- State Key Laboratory of Transient Optics and Photonics, Xi’an Institute of Optics and Precision Mechanics, Chinese Academy of Sciences, Xi’an 710119, China; (L.Z.); (Y.R.); (Y.L.)
- University of Chinese Academy of Sciences, Beijing 100049, China
| | - Xiaochen Sun
- State Key Laboratory of Transient Optics and Photonics, Xi’an Institute of Optics and Precision Mechanics, Chinese Academy of Sciences, Xi’an 710119, China; (L.Z.); (Y.R.); (Y.L.)
- University of Chinese Academy of Sciences, Beijing 100049, China
| |
Collapse
|
3
|
Li K, Zhu J, Duan Q, Hou X. High-efficiency dual-layer grating coupler for vertical fiber-chip coupling in two polarizations. JOURNAL OF THE OPTICAL SOCIETY OF AMERICA. A, OPTICS, IMAGE SCIENCE, AND VISION 2023; 40:1022-1028. [PMID: 37706755 DOI: 10.1364/josaa.487739] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/15/2023] [Accepted: 03/31/2023] [Indexed: 09/15/2023]
Abstract
Efficient coupling between optical fibers and high-index-contrast silicon waveguides is essential for the development of integrated nanophotonics. Herein, a high-efficiency dual-layer grating coupler is demonstrated for vertical polarization-diversity fiber-chip coupling. The two waveguide layers are orthogonally distributed and designed for y- and x-polarized L P 01 fiber modes, respectively. Each layer consists of two 1D stacked gratings, allowing for both perfectly vertical coupling and high coupling directionality. The gratings are optimized using the particle swarm algorithm with a preset varying trend of parameters to thin out the optimization variables. The interlayer thickness is determined to ensure efficient coupling of both polarizations. The optimized results exhibit record highs of 92% (-0.38d B) and 85% (-0.72d B) 3D finite-difference time-domain simulation efficiencies for y and x polarizations, respectively. The polarization-dependent loss (PDL) is below 2 dB in a 160 nm spectral bandwidth with cross talk between the two polarizations less than -24d B. Fabrication imperfections are also investigated. Dimensional offsets of ±10n m in etching width and ±8 nm in lateral shift are tolerated for a 1 dB loss penalty. The proposed structure offers an ultimate solution for polarization diversity coupling schemes in silicon photonics with high directionality, low PDL, and a possibility to vertically couple.
Collapse
|
4
|
Gupta R, Singh R, Gehlot A, Akram SV, Yadav N, Brajpuriya R, Yadav A, Wu Y, Zheng H, Biswas A, Suhir E, Yadav VS, Kumar T, Verma AS. Silicon photonics interfaced with microelectronics for integrated photonic quantum technologies: a new era in advanced quantum computers and quantum communications? NANOSCALE 2023; 15:4682-4693. [PMID: 36779637 DOI: 10.1039/d2nr05610k] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/18/2023]
Abstract
Silicon photonics is rapidly evolving as an advanced chip framework for implementing quantum technologies. With the help of silicon photonics, general-purpose programmable networks with hundreds of discrete components have been developed. These networks can compute quantum states generated on-chip as well as more extraordinary functions like quantum transmission and random number generation. In particular, the interfacing of silicon photonics with complementary metal oxide semiconductor (CMOS) microelectronics enables us to build miniaturized quantum devices for next-generation sensing, communication, and generating randomness for assembling quantum computers. In this review, we assess the significance of silicon photonics and its interfacing with microelectronics for achieving the technology milestones in the next generation of quantum computers and quantum communication. To this end, especially, we have provided an overview of the mechanism of a homodyne detector and the latest state-of-the-art of measuring squeezed light along with its integration on a photonic chip. Finally, we present an outlook on future studies that are considered beneficial for the wide implementation of silicon photonics for distinct data-driven applications with maximum throughput.
Collapse
Affiliation(s)
- Rajeev Gupta
- Department of Applied Sciences, School of Engineering, University of Petroleum & Energy Studies, Dehradun, Uttarakhand, 248007, India.
| | - Rajesh Singh
- Division of Research and Innovation, Uttaranchal Institute of Technology, Uttaranchal University, Dehradun-248007, India
- Department of Project Management, Universidad Internacional Iberoamericana, Campeche C.P. 24560, México
| | - Anita Gehlot
- Division of Research and Innovation, Uttaranchal Institute of Technology, Uttaranchal University, Dehradun-248007, India
- Department of Project Management, Universidad Internacional Iberoamericana, Campeche C.P. 24560, México
| | - Shaik Vaseem Akram
- Division of Research and Innovation, Uttaranchal Institute of Technology, Uttaranchal University, Dehradun-248007, India
| | - Neha Yadav
- Center for Advanced Laser Manufacturing (CALM), Shandong University of Technology, Zibo, 255000, P.R. China.
| | - Ranjeet Brajpuriya
- Department of Applied Sciences, School of Engineering, University of Petroleum & Energy Studies, Dehradun, Uttarakhand, 248007, India.
| | - Ashish Yadav
- Center for Advanced Laser Manufacturing (CALM), Shandong University of Technology, Zibo, 255000, P.R. China.
| | - Yongling Wu
- Center for Advanced Laser Manufacturing (CALM), Shandong University of Technology, Zibo, 255000, P.R. China.
| | - Hongyu Zheng
- Center for Advanced Laser Manufacturing (CALM), Shandong University of Technology, Zibo, 255000, P.R. China.
| | - Abhijit Biswas
- USA Prime Biotech LLC, 1330 NW 6th Street, Suite A2, Gainesville, FL 32601, USA
| | - Ephraim Suhir
- Department of Mechanical and Materials Engineering and Department of Electrical and Computer Engineering, Portland State University, Portland, OR, USA
| | - Vikram Singh Yadav
- Department of Applied Sciences, Bundelkhand Institute of Engineering and Technology, Jhansi, India
| | - Tanuj Kumar
- Department of Nanoscience and materials, Central University of Jammu, Jammu, 181143, India
| | - Ajay Singh Verma
- Division of Research & Innovation, School of Applied and Life Sciences, Uttaranchal University, Dehradun-248007, India
- University Centre for Research & Development, Department of Physics, Chandigarh University, Mohali, Punjab-140413, India
| |
Collapse
|
5
|
Badamchi B, Hsu WC, Ahmed Simon AA, Yin Chi Z, Manzi J, Mitkova M, Wang AX, Subbaraman H. Ultra-compact hybrid silicon:chalcogenide waveguide temperature sensor. OPTICS EXPRESS 2022; 30:28470-28478. [PMID: 36299041 DOI: 10.1364/oe.462691] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/29/2022] [Accepted: 07/06/2022] [Indexed: 06/16/2023]
Abstract
We demonstrate a real-time, reusable, and reversible integrated optical sensor for temperature monitoring within harsh environments. The sensor architecture combines the phase change property of chalcogenide glasses (ChG) with the high-density integration advantages of high index silicon waveguides. To demonstrate sensor feasibility, ChG composition Ge40S60, which is characterized by a sharp phase transition from amorphous to crystalline phase around 415 °C, is deposited over a 50 µm section of a single mode optical waveguide. The phase transition changes the behavior of Ge40S60 from a low loss to high loss material, thus significantly affecting the hybrid waveguide loss around the phase transition temperature. A transmission power drop of over 40dB in the crystalline phase compared to the amorphous phase is experimentally measured. Moreover, we recover the amorphous phase through the application of an electrical pulse, thus showing the reversible nature of our compact temperature sensor. Through integrating multiple compositions of ChG with well-defined phases transition temperatures over a silicon waveguide array, it is possible to determine, in real-time, the temperature evolution within a harsh environment, such as within a nuclear reactor cladding.
Collapse
|
6
|
Free-Space Applications of Silicon Photonics: A Review. MICROMACHINES 2022; 13:mi13070990. [PMID: 35888807 PMCID: PMC9322159 DOI: 10.3390/mi13070990] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 05/30/2022] [Revised: 06/22/2022] [Accepted: 06/23/2022] [Indexed: 01/25/2023]
Abstract
Silicon photonics has recently expanded its applications to delivering free-space emissions for detecting or manipulating external objects. The most notable example is the silicon optical phased array, which can steer a free-space beam to achieve a chip-scale solid-state LiDAR. Other examples include free-space optical communication, quantum photonics, imaging systems, and optogenetic probes. In contrast to the conventional optical system consisting of bulk optics, silicon photonics miniaturizes an optical system into a photonic chip with many functional waveguiding components. By leveraging the mature and monolithic CMOS process, silicon photonics enables high-volume production, scalability, reconfigurability, and parallelism. In this paper, we review the recent advances in beam steering technologies based on silicon photonics, including optical phased arrays, focal plane arrays, and dispersive grating diffraction. Various beam-shaping technologies for generating collimated, focused, Bessel, and vortex beams are also discussed. We conclude with an outlook of the promises and challenges for the free-space applications of silicon photonics.
Collapse
|
7
|
Dushaq G, Paredes B, Villegas JE, Tamalampudi SR, Rasras M. On-chip integration of 2D Van der Waals germanium phosphide (GeP) for active silicon photonics devices. OPTICS EXPRESS 2022; 30:15986-15997. [PMID: 36221452 DOI: 10.1364/oe.457242] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/28/2022] [Accepted: 04/11/2022] [Indexed: 06/16/2023]
Abstract
The outstanding performance and facile processability turn two-dimensional materials (2DMs) into the most sought-after class of semiconductors for optoelectronics applications. Yet, significant progress has been made toward the hybrid integration of these materials on silicon photonics (SiPh) platforms for a wide range of mid-infrared (MIR) applications. However, realizing 2D materials with a strong optical response in the NIR-MIR and excellent air stability is still a long-term goal. Here, we report a waveguide integrated photodetector based on a novel 2D GeP. This material uniquely combines narrow and wide tunable bandgap energies (0.51-1.68 eV), offering a broadband operation from visible to MIR spectral range. In a significant advantage over graphene devices, hybrid Si/GeP waveguide photodetectors work under bias with a low dark current of few nano-amps and demonstrate excellent stability and reproducibility. Additionally, 65 nm thick GeP devices integrated on silicon waveguides exhibit a remarkable photoresponsivity of 0.54 A/W and attain high external quantum efficiency of ∼ 51.3% under 1310 nm light and at room temperature. Furthermore, a measured absorption coefficient of 1.54 ± 0.3 dB/µm at 1310 nm suggests the potential of 2D GeP as an alternative infrared material with broad optical tunability and dynamic stability suitable for advanced optoelectronic integration.
Collapse
|
8
|
Zhou Y, Lv D, Bi D, Wu L, Wang R, Ma S, Zhang EX, Fleetwood DM, Wu A. Radiation-hardened silicon photonic passive devices on a 3 µm waveguide platform under gamma and proton irradiation. OPTICS EXPRESS 2022; 30:16921-16930. [PMID: 36221525 DOI: 10.1364/oe.453903] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/19/2022] [Accepted: 04/20/2022] [Indexed: 06/16/2023]
Abstract
Silicon photonics is considered to be an ideal solution as optical interconnect in radiation environments. Our previous study has demonstrated experimentally that radiation responses of device are related to waveguide size, and devices with thick top silicon waveguide layers are expected to be less sensitive to irradiation. Here, we design radiation-resistant arrayed waveguide gratings and Mach-Zehnder interferometers based on silicon-on-insulator with 3 µm-thick silicon optical waveguide platform. The devices are exposed to 60Co γ-ray irradiation up to 41 Mrad(Si) and 170-keV proton irradiation with total fluences from 1×1013 to 1×1016 p/cm2 to evaluate performance after irradiation. The results show that these devices can function well and have potential application in harsh radiation environments.
Collapse
|
9
|
Nelan S, Mercante A, Hurley C, Shi S, Yao P, Shopp B, Prather DW. Compact thin film lithium niobate folded intensity modulator using a waveguide crossing. OPTICS EXPRESS 2022; 30:9193-9207. [PMID: 35299354 DOI: 10.1364/oe.453050] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/05/2022] [Accepted: 02/24/2022] [Indexed: 06/14/2023]
Abstract
A small footprint, low voltage and wide bandwidth electro-optic modulator is critical for applications ranging from optical communications to analog photonic links, and the integration of thin-film lithium niobate with photonic integrated circuit (PIC) compatible materials remains paramount. Here, a hybrid silicon nitride and lithium niobate folded electro-optic Mach Zehnder modulator (MZM) which incorporates a waveguide crossing and 3 dB multimode interference (MMI) couplers for splitting and combining light is reported. This modulator has an effective interaction region length of 10 mm and shows a DC half wave voltage of roughly 4.0 V, or a modulation efficiency (Vπ ·L) of roughly 4 V·cm. Furthermore, the device demonstrates a power extinction ratio of roughly 23 dB and shows .08 dB/GHz optical sideband power roll-off with index matching fluid up to 110 GHz, with a 3-dB bandwidth of 37.5 GHz.
Collapse
|
10
|
Zhou Y, Bi D, Wang S, Wu L, Huang Y, Zhang E, Fleetwood DM, Wu A. High energy irradiation effects on silicon photonic passive devices. OPTICS EXPRESS 2022; 30:4017-4027. [PMID: 35209648 DOI: 10.1364/oe.447160] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/29/2021] [Accepted: 01/12/2022] [Indexed: 06/14/2023]
Abstract
In this work, the radiation responses of silicon photonic passive devices built in silicon-on-insulator (SOI) technology are investigated through high energy neutron and 60Co γ-ray irradiation. The wavelengths of both micro-ring resonators (MRRs) and Mach-Zehnder interferometers (MZIs) exhibit blue shifts after high-energy neutron irradiation to a fluence of 1×1012 n/cm2; the blue shift is smaller in MZI devices than in MRRs due to different waveguide widths. Devices with SiO2 upper cladding layer show strong tolerance to irradiation. Neutron irradiation leads to slight changes in the crystal symmetry in the Si cores of the optical devices and accelerated oxidization for devices without SiO2 cladding. A 2-µm top cladding of SiO2 layer significantly improves the radiation tolerance of these passive photonic devices.
Collapse
|
11
|
Zhang Y, Liu S, Zhai W, Peng C, Wang Z, Feng J, Guo J. Reconfigurable spot size converter for the silicon photonics integrated circuit. OPTICS EXPRESS 2021; 29:37703-37711. [PMID: 34808837 DOI: 10.1364/oe.438652] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/29/2021] [Accepted: 10/18/2021] [Indexed: 06/13/2023]
Abstract
Spot size converter (SSC) plays a role of paramount importance in the silicon photonics integrated circuit. In this article, we report the design of a reconfigurable spot size converter used in the hybrid integration of a DFB laser diode with a silicon photonic waveguide. Our SSC consists of subwavelength gratings and thermal phase shifters. Four subwavelength grating tips are used to improve horizontal misalignment tolerance. Meanwhile, the phase mismatch between two input waveguides is compensated by phase shifters to minimize insertion losses. Our simulated result has yielded a minimum insertion loss of 0.63 dB and an improvement of the horizontal misalignment from ±0.65 µm to ±1.69 µm for 1 dB excess insertion loss at the wavelength of 1310 nm. The phase shifters are designed to compensate any phase error in both the fabrication and bonding processes, which provides a completely new edge-coupling strategy for the silicon photonics integrated circuit.
Collapse
|
12
|
Schuler S, Muench JE, Ruocco A, Balci O, Thourhout DV, Sorianello V, Romagnoli M, Watanabe K, Taniguchi T, Goykhman I, Ferrari AC, Mueller T. High-responsivity graphene photodetectors integrated on silicon microring resonators. Nat Commun 2021; 12:3733. [PMID: 34145226 PMCID: PMC8213857 DOI: 10.1038/s41467-021-23436-x] [Citation(s) in RCA: 20] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/05/2020] [Accepted: 04/14/2021] [Indexed: 02/05/2023] Open
Abstract
Graphene integrated photonics provides several advantages over conventional Si photonics. Single layer graphene (SLG) enables fast, broadband, and energy-efficient electro-optic modulators, optical switches and photodetectors (GPDs), and is compatible with any optical waveguide. The last major barrier to SLG-based optical receivers lies in the current GPDs' low responsivity when compared to conventional PDs. Here we overcome this by integrating a photo-thermoelectric GPD with a Si microring resonator. Under critical coupling, we achieve >90% light absorption in a ~6 μm SLG channel along a Si waveguide. Cavity-enhanced light-matter interactions cause carriers in SLG to reach ~400 K for an input power ~0.6 mW, resulting in a voltage responsivity ~90 V/W, with a receiver sensitivity enabling our GPDs to operate at a 10-9 bit-error rate, on par with mature semiconductor technology, but with a natural generation of a voltage, rather than a current, thus removing the need for transimpedance amplification, with a reduction of energy-per-bit, cost, and foot-print.
Collapse
Affiliation(s)
- S Schuler
- Vienna University of Technology, Institute of Photonics, Vienna, Austria
- Cambridge Graphene Centre, University of Cambridge, Cambridge, UK
| | - J E Muench
- Cambridge Graphene Centre, University of Cambridge, Cambridge, UK
| | - A Ruocco
- Cambridge Graphene Centre, University of Cambridge, Cambridge, UK
| | - O Balci
- Cambridge Graphene Centre, University of Cambridge, Cambridge, UK
| | - D van Thourhout
- Ghent University-IMEC, Photonics Research Group, Gent, Belgium
| | - V Sorianello
- Consorzio Nazionale per le Telecomunicazioni and Inphotec, Pisa, Italy
| | - M Romagnoli
- Consorzio Nazionale per le Telecomunicazioni and Inphotec, Pisa, Italy
| | - K Watanabe
- National Institute for Materials Science, Tsukuba, Japan
| | - T Taniguchi
- National Institute for Materials Science, Tsukuba, Japan
| | - I Goykhman
- Cambridge Graphene Centre, University of Cambridge, Cambridge, UK
- Technion-Israel Institute of Technology, Haifa, Israel
| | - A C Ferrari
- Cambridge Graphene Centre, University of Cambridge, Cambridge, UK.
| | - T Mueller
- Vienna University of Technology, Institute of Photonics, Vienna, Austria.
| |
Collapse
|
13
|
John JW, Dhyani V, Singh S, Jakhar A, Sarkar A, Das S, Ray SK. Low-noise, high-detectivity, polarization-sensitive, room-temperature infrared photodetectors based on Ge quantum dot-decorated Si-on-insulator nanowire field-effect transistors. NANOTECHNOLOGY 2021; 32:315205. [PMID: 33845466 DOI: 10.1088/1361-6528/abf6f0] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/25/2021] [Accepted: 04/12/2021] [Indexed: 06/12/2023]
Abstract
A CMOS-compatible infrared (IR; 1200-1700 nm) detector based on Ge quantum dots (QDs) decorated on a single Si-nanowire channel on a silicon-on-insulator (SOI) platform with a superior detectivity at room temperature is presented. The spectral response of a single nanowire device measured in a back-gated field-effect transistor geometry displays a very high value of peak detectivity ∼9.33 × 1011Jones at ∼1500 nm with a relatively low dark current (∼20 pA), which is attributed to the fully depleted Si nanowire channel on SOI substrates. The noise power spectrum of the devices exhibits a1/fγ,with the exponent,γshowing two different values of 0.9 and 1.8 owing to mobility fluctuations and generation-recombination of carriers, respectively. Ge QD-decorated nanowire devices exhibit a novel polarization anisotropy with a remarkably high photoconductive gain of ∼104. The superior performance of a Ge QDs/Si nanowire phototransistor in IR wavelengths is potentially attractive to integrate electro-optical devices into Si for on-chip optical communications.
Collapse
Affiliation(s)
- John Wellington John
- Center for Applied Research in Electronics, Indian Institute of Technology Delhi, New Delhi-110061, India
| | - Veerendra Dhyani
- Center for Applied Research in Electronics, Indian Institute of Technology Delhi, New Delhi-110061, India
| | - Sudarshan Singh
- Department of Physics, Indian Institute of Technology Kharagpur, Kharagpur-721302, India
| | - Alka Jakhar
- Center for Applied Research in Electronics, Indian Institute of Technology Delhi, New Delhi-110061, India
| | - Arijit Sarkar
- Advanced Technology Development Center, Indian Institute of Technology Kharagpur, Kharagpur-721302, India
| | - Samaresh Das
- Center for Applied Research in Electronics, Indian Institute of Technology Delhi, New Delhi-110061, India
| | - Samit K Ray
- Department of Physics, Indian Institute of Technology Kharagpur, Kharagpur-721302, India
- S N Bose National Centre for Basic Sciences, Salt Lake City, Kolkata-106, India
| |
Collapse
|
14
|
Zhou J, Liu M, Lu M, Lin PT. Mid-infrared frequency doubling using strip-loaded silicon nitride on epitaxial barium titanate thin film waveguides. OPTICS LETTERS 2020; 45:6358-6361. [PMID: 33258811 DOI: 10.1364/ol.403760] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/03/2020] [Accepted: 10/05/2020] [Indexed: 06/12/2023]
Abstract
Broadband mid-infrared (mid-IR) frequency doubling was demonstrated using nonlinear barium titanate (BTO) thin films. The device has a strip-loaded waveguide structure consisting of top silicon nitride (SiN) strips and an underneath BTO guiding layer. The epitaxial BTO was deposited on a strontium titanate (STO) substrate by pulsed-laser deposition. Through a SiN grating coupler, the pumping mid-IR light at wavelength λ=3.30-3.45µm was coupled into the nonlinear BTO layer, where the spectrum of the near-infrared (NIR) second-harmonic generation was characterized. The developed BTO waveguides provide a platform for mid-IR nonlinear integrated photonics and on-chip quantum optics.
Collapse
|
15
|
Shi Y, Wu Z, Xiang Z, Chen P, Li C, Zhou H, Dong X, Gou J, Wang J, Jiang Y. Silicon-based PbS-CQDs infrared photodetector with high sensitivity and fast response. NANOTECHNOLOGY 2020; 31:485206. [PMID: 32931466 DOI: 10.1088/1361-6528/abb105] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/11/2023]
Abstract
Silicon-based photodetectors as the main force in visible and near-infrared detection devices have been deeply embedded in modern technology and human society, but due to the characteristics of silicon itself, its response wavelength is generally less than 1100 nm. It is an interesting study to combine the state-of-art silicon processing with emerging infrared-sensitive Lead sulfide colloidal quantum dots (PbS-CQDs) to produce a photodetector that can detect infrared light. Here, we demonstrated a silicon-compatible photodetector that could be integrated on-chip, and also sensitive to infrared light which is owing to a PbS-CQDs absorption layer with tunable bandgap. The device exhibit extremely high gain which reaches maximum detectivity [Formula: see text], fast response 211/558 μs, and extremely high external quantum efficiency [Formula: see text], which is owing to new architecture and reasonable ligand exchange options. The performance of the device originates from the new architecture, that is, using the photovoltaic voltage generated by the surface of PbS-CQDs to change the width of the depletion layer to achieve detection. Besides, the performance improvement of devices comes from the addition of PbS-CQDs (Ethanedithiol treated) layer, which effectively reduces the fall time and makes the device expected to work at higher frequencies. Our work paves the way for the realization of cost-efficient high-performance silicon compatible infrared optoelectronic devices.
Collapse
Affiliation(s)
- Yuanlin Shi
- School of Optoelectronic Science and Engineering, University of Electronic Science and Technology of China, Chengdu 610054, People's Republic of China
| | | | | | | | | | | | | | | | | | | |
Collapse
|
16
|
Li Y, Liu FR, Han G, Chen QY, Zhao ZP, Xie XX, Huang Y, Yuan YP. Design of low loss 1 × 1 and 1 × 2 phase-change optical switches with different crystalline phases of Ge 2Sb 2Te 5 films. NANOTECHNOLOGY 2020; 31:455206. [PMID: 32707570 DOI: 10.1088/1361-6528/aba928] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/11/2023]
Abstract
On-chip photonics devices relying on the weak, volatile thermo-optic or electro-optic effects of silicon usually suffer from high insertion loss (IL) and a low refractive index coefficient. In this paper, we designed two novel 1 × 1 and 1 × 2 phase-change optical switches based on a signal-mode Si waveguide integrated with a Ge2Sb2Te5 (GST) top clad layer, respectively. The three-state switch including amorphous GST (a-GST), face centered cubic crystalline phase (FCC-GST) and hexagonal crystalline phase (HCP-GST) operated by utilizing the dramatic difference in the optical constants between the amorphous and two crystalline phases of GST. In the case of the 1 × 1 optical switch, an extinction ratio (ER) of 8.9 dB and an extremely low IL of 0.8 dB were achieved using an optimum GST length of only 2 μm. While for the 1 × 2 optical switch, low ILs in the range of 0.15 ∼ 0.35 dB for both 'cross' (a-GST) and 'bar' (FCC-GST and HCP-GST) states were also obtained. Additionally, we found that both ILs and mode losses of the switch with HCP-GST were about half lower than those with FCC-GST, which means FCC-GST could be instituted by HCP-GST in the traditional ovonic switch with the consideration of low loss. This research provides the fundamental understanding for the realization of low loss and non-volatile Si-GST hybrid optical switches, with potential for future communication networks.
Collapse
Affiliation(s)
- Y Li
- Key Laboratory of Trans-scale Laser Manufacturing, (Beijing University of Technology), Ministry of Education, Beijing 100124 People's Republic of China. Beijing Engineering Research Center of Laser Technology, Beijing University of Technology, Beijing 100124 People's Republic of China. Institute of Laser Engineering, Faculty of Materials and Manufacturing, Beijing University of Technology, Beijing 100124 People's Republic of China
| | | | | | | | | | | | | | | |
Collapse
|
17
|
Silicon Integrated Nanophotonic Devices for On-Chip Multi-Mode Interconnects. APPLIED SCIENCES-BASEL 2020. [DOI: 10.3390/app10186365] [Citation(s) in RCA: 23] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Mode-division multiplexing (MDM) technology has drawn tremendous attention for its ability to expand the link capacity within a single-wavelength carrier, paving the way for large-scale on-chip data communications. In the MDM system, the signals are carried by a series of higher-order modes in a multi-mode bus waveguide. Hence, it is essential to develop on-chip mode-handling devices. Silicon-on-insulator (SOI) has been considered as a promising platform to realize MDM since it provides an ultra-high-index contrast and mature fabrication processes. In this paper, we review the recent progresses on silicon integrated nanophotonic devices for MDM applications. We firstly discuss the working principles and device configurations of mode (de)multiplexers. In the second section, we summarize the multi-mode routing devices, including multi-mode bends, multi-mode crossings and multi-mode splitters. The inverse-designed multi-mode devices are then discussed in the third section. We also provide a discussion about the emerging reconfigurable MDM devices in the fourth section. Finally, we offer our outlook of the development prospects for on-chip multi-mode photonics.
Collapse
|
18
|
Metal-Semiconductor-Metal GeSn Photodetectors on Silicon for Short-Wave Infrared Applications. MICROMACHINES 2020; 11:mi11090795. [PMID: 32839407 PMCID: PMC7570010 DOI: 10.3390/mi11090795] [Citation(s) in RCA: 17] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 07/25/2020] [Revised: 08/19/2020] [Accepted: 08/19/2020] [Indexed: 11/17/2022]
Abstract
Metal-semiconductor-metal photodetectors (MSM PDs) are effective for monolithic integration with other optical components of the photonic circuits because of the planar fabrication technique. In this article, we present the design, growth, and characterization of GeSn MSM PDs that are suitable for photonic integrated circuits. The introduction of 4% Sn in the GeSn active region also reduces the direct bandgap and shows a redshift in the optical responsivity spectra, which can extend up to 1800 nm wavelength, which means it can cover the entire telecommunication bands. The spectral responsivity increases with an increase in bias voltage caused by the high electric field, which enhances the carrier generation rate and the carrier collection efficiency. Therefore, the GeSn MSM PDs can be a suitable device for a wide range of short-wave infrared (SWIR) applications.
Collapse
|
19
|
Dushaq G, Paredes B, Rasras M. Strong enhancement of direct transition photoluminescence at room temperature for highly tensile-strained Ge decorated using 5 nm gold nanoparticles. NANOTECHNOLOGY 2020; 31:315201. [PMID: 32303009 DOI: 10.1088/1361-6528/ab8a8d] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/11/2023]
Abstract
Strain engineering of germanium has recently attracted tremendous research interest. The primary goal of this approach is to exploit mechanical strain to tune the electrical and optical properties of Ge to ultimately achieve an on-chip light source compatible with silicon technology. Additionally, this can result in enhanced electrical performance for high-speed optoelectronic applications. In this paper, we demonstrate the formation of highly tensile-strained Ge islands grown on a pre-patterned (110) GaAs substrate using a depth controlled nanoindentation process. Results show that a biaxial tensile strain, up to ∼2%, can be transferred from the mechanically stamped substrate to Ge islands by optimizing the parameters of the nanoindentation process. We verified our measurements by observing the islands' photoluminescence (PL) emission properties. A strong emission at room-temperature was observed around the wavelength of 1.9 µm (650 meV). This strain-induced redshift of the PL spectra is consistent with theoretical predictions, revealing a direct Ge bandgap formation. Furthermore, we demonstrate a significant 6.5x enhancement in the PL emission signal of the direct-transition when the Ge islands are decorated by 5 nm gold nanoparticles. This is attributed to a longer optical path length interaction and a plasmonic induced high-field enhancement which increases the light absorption in the Ge islands. Furthermore, results show that GNPs can significantly modulate the energy band structure and the carrier's transportation at the nanoscale metal-germanium Schottky interface. This maskless physical approach can offer a pathway towards a practical CMOS-compatible integrated laser. Additionally, it opens possibilities for designing innovative optoelectronic devices.
Collapse
|
20
|
Wang X, Yu H, Qiu H, Zhang Q, Fu Z, Xia P, Chen B, Guo X, Wang Y, Jiang X, Yang J. Hitless and gridless reconfigurable optical add drop (de)multiplexer based on looped waveguide sidewall Bragg gratings on silicon. OPTICS EXPRESS 2020; 28:14461-14475. [PMID: 32403486 DOI: 10.1364/oe.390218] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/12/2020] [Accepted: 04/18/2020] [Indexed: 06/11/2023]
Abstract
Reconfigurable optical add-drop filters in future intelligent and software controllable wavelength division multiplexing networks should support hitless wavelength switching and gridless bandwidth tuning. The hitless switching implies that the central wavelength of one channel can be shifted without disturbing data transmissions of other channels, while the gridless tuning means that the filter bandwidth can be adjusted continuously. Despite a lot of efforts, very few integrated optical filters simultaneously support the hitless switching of central wavelength and the gridless tuning of bandwidth. In this work, we demonstrate a hitless add-drop filter with gridless bandwidth tunability on the silicon-on-insulator (SOI) platform. The filter comprises the two identical multimode anti-symmetric waveguide Bragg gratings (MASWBG) which are connected to a loop. The phase apodization technique is utilized to weaken the intrinsic sidelobe interference of grating-based devices. By sequentially manipulating central wavelengths of the two MASWBGs with the thermo-optical effect, we can reconfigure the spectral response of the filter gridlessly and hitlessly. Specifically, the central wavelength of the device is shifted by 14.5 nm, while its 3 dB bandwidth is tuned from 0.2 nm to 2.4 nm. The dropping loss and the sidelobe suppression ratio (SLSR) are dependent on the bandwidth selected. Measured variation ranges of dropping loss and SLSR are from -1.2 dB to -2.5 dB and from 12.8 dB to 21.4 dB, respectively. The hitless wavelength switching is verified by a data transmission measurement at a bit rate of 25 Gbps.
Collapse
|
21
|
Chack D, Hassan S, Qasim M. Broadband and low crosstalk silicon on-chip mode converter and demultiplexer for mode division multiplexing. APPLIED OPTICS 2020; 59:3652-3659. [PMID: 32400481 DOI: 10.1364/ao.390085] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/07/2020] [Accepted: 03/13/2020] [Indexed: 06/11/2023]
Abstract
In this paper, a compact and broadband mode converter and demultiplexer based on multimode interference (MMI) is designed and experimentally demonstrated on silicon-on-insulator. We have designed a mode converter using cascaded MMI to convert the fundamental mode into a higher-order (first-order mode) and vice versa. Subsequently, we have demonstrated an on-chip two-mode demultiplexer with a compact footprint and low loss. The proposed mode demultiplexer shows low insertion loss (0.22 dB for ${{\rm TE}_0}$TE0 and 0.36 dB for ${{\rm TE}_1}$TE1 mode) and crosstalk (${-}{25.2}\;{\rm dB}$-25.2dB for ${{\rm TE}_0}$TE0 and ${-}{24.4}\;{\rm dB}$-24.4dB for ${{\rm TE}_1}$TE1 mode) at wavelength 1550 nm using the eigenmode expansion method. Moreover, the device supports a broad bandwidth having crosstalk ${ \lt } {-} {20}\;{\rm dB}$<-20dB over a wavelength range of 1520-1580 nm. The proposed device can be used in mode division multiplexing for photonic network-on-chip.
Collapse
|
22
|
Abstract
Silicon photonics has drawn increasing attention in the past few decades and is a promising key technology for future daily applications due to its various merits including ultra-low cost, high integration density owing to the high refractive index of silicon, and compatibility with current semiconductor fabrication process. Optical interconnects is an important issue in silicon photonic integrated circuits for transmitting light, and fiber-to-chip optical interconnects is vital in application scenarios such as data centers and optical transmission systems. There are mainly two categories of fiber-to-chip optical coupling: off-plane coupling and in-plane coupling. Grating couplers work under the former category, while edge couplers function as in-plane coupling. In this paper, we mainly focus on edge couplers in silicon photonic integrated circuits. We deliver an introduction to the research background, operation mechanisms, and design principles of silicon photonic edge couplers. The state-of-the-art of edge couplers is reviewed according to the different structural configurations of the device, while identifying the performance, fabrication feasibility, and applications. In addition, a brief comparison between edge couplers and grating couplers is conducted. Packaging issues are also discussed, and several prospective techniques for further improvements of edge couplers are proposed.
Collapse
|
23
|
Hu H, Zhang H, Zhou L, Xu J, Lu L, Chen J, Rahman BMA. Contra-directional switching enabled by Si-GST grating. OPTICS EXPRESS 2020; 28:1574-1584. [PMID: 32121865 DOI: 10.1364/oe.381502] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/28/2019] [Accepted: 01/02/2020] [Indexed: 06/10/2023]
Abstract
We present the design, simulation, and experimental demonstration of a Si-GST grating assisted contra-directional coupler for optical switching. The effective refractive index of the GST-loaded silicon waveguide changes significantly when the GST is switched from the amorphous state to the crystalline state, allowing for large tuning of the propagation constant. The two coupled waveguides are designed to satisfy the phase-match condition only at the amorphous state to achieve Bragg reflection at the drop-port. Experimental results show that the device insertion loss is less than 5 dB and the extinction ratio is more than 15 dB with an operation bandwidth of 2.2 nm around the 1576 nm operating wavelength. Due to the nonvolatile property of GST, there is no static power consumption to maintain the two states. It is the first demonstration of a GST-enabled grating coupler that can be switched by phase change material.
Collapse
|
24
|
Zhao P, Zeng Z, Yang N, Gao Q, Tang B, Li Z, Yan J, Jiang W. Correlation between driving signal reflection on electrodes and performance variation of silicon Mach-Zehnder modulators. OPTICS EXPRESS 2019; 27:35349-35361. [PMID: 31878705 DOI: 10.1364/oe.27.035349] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/10/2019] [Accepted: 11/04/2019] [Indexed: 06/10/2023]
Abstract
We study the correlations between the driving signal reflection on the traveling wave electrodes and the modulated signal characteristics of silicon Mach-Zehnder modulators (MZM). Correlation coefficients are introduced for systematic and quantitative analysis. The signal-to-noise ratio, extinction ratio, and bit error rate show similar correlation behaviors with the mean reflection magnitude over proper frequency ranges, whereas the correlation behaviors of the temporal parameters can be complex. Partial correlation coefficients can be introduced to help remove the influence of other factors. Some relevant fabrication variation scenarios in the underlying structures are discussed, and potential approaches to mitigating the effects of such variations are suggested.
Collapse
|
25
|
Muench JE, Ruocco A, Giambra MA, Miseikis V, Zhang D, Wang J, Watson HFY, Park GC, Akhavan S, Sorianello V, Midrio M, Tomadin A, Coletti C, Romagnoli M, Ferrari AC, Goykhman I. Waveguide-Integrated, Plasmonic Enhanced Graphene Photodetectors. NANO LETTERS 2019; 19:7632-7644. [PMID: 31536362 DOI: 10.1021/acs.nanolett.9b02238] [Citation(s) in RCA: 38] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/17/2023]
Abstract
We present a micrometer-scale, on-chip integrated, plasmonic enhanced graphene photodetector (GPD) for telecom wavelengths operating at zero dark current. The GPD is designed to directly generate a photovoltage by the photothermoelectric effect. It is made of chemical vapor deposited single layer graphene, and has an external responsivity ∼12.2 V/W with a 3 dB bandwidth ∼42 GHz. We utilize Au split-gates to electrostatically create a p-n-junction and simultaneously guide a surface plasmon polariton gap-mode. This increases the light-graphene interaction and optical absorption and results in an increased electronic temperature and steeper temperature gradient across the GPD channel. This paves the way to compact, on-chip integrated, power-efficient graphene based photodetectors for receivers in tele- and datacom modules.
Collapse
Affiliation(s)
- Jakob E Muench
- Cambridge Graphene Centre , University of Cambridge , Cambridge CB3 0FA , United Kingdom
| | - Alfonso Ruocco
- Cambridge Graphene Centre , University of Cambridge , Cambridge CB3 0FA , United Kingdom
| | - Marco A Giambra
- Consorzio Nazionale per le Telecomunicazioni , 56124 Pisa , Italy
| | - Vaidotas Miseikis
- Consorzio Nazionale per le Telecomunicazioni , 56124 Pisa , Italy
- Center for Nanotechnology Innovation @ NEST , Istituto Italiano di Tecnologia , 56127 Pisa , Italy
- Graphene Labs , Istituto Italiano di Tecnologia , 16163 Genova , Italy
| | - Dengke Zhang
- Cambridge Graphene Centre , University of Cambridge , Cambridge CB3 0FA , United Kingdom
| | - Junjia Wang
- Cambridge Graphene Centre , University of Cambridge , Cambridge CB3 0FA , United Kingdom
| | - Hannah F Y Watson
- Cambridge Graphene Centre , University of Cambridge , Cambridge CB3 0FA , United Kingdom
| | - Gyeong C Park
- Cambridge Graphene Centre , University of Cambridge , Cambridge CB3 0FA , United Kingdom
| | - Shahab Akhavan
- Cambridge Graphene Centre , University of Cambridge , Cambridge CB3 0FA , United Kingdom
| | - Vito Sorianello
- Consorzio Nazionale per le Telecomunicazioni , 56124 Pisa , Italy
| | - Michele Midrio
- Consorzio Nazionale per le Telecomunicazioni , University of Udine , 33100 Udine , Italy
| | - Andrea Tomadin
- Dipartimento di Fisica , Università di Pisa , Largo Bruno Pontecorvo 3 , 56127 Pisa , Italy
| | - Camilla Coletti
- Center for Nanotechnology Innovation @ NEST , Istituto Italiano di Tecnologia , 56127 Pisa , Italy
- Graphene Labs , Istituto Italiano di Tecnologia , 16163 Genova , Italy
| | - Marco Romagnoli
- Consorzio Nazionale per le Telecomunicazioni , 56124 Pisa , Italy
| | - Andrea C Ferrari
- Cambridge Graphene Centre , University of Cambridge , Cambridge CB3 0FA , United Kingdom
| | - Ilya Goykhman
- Micro Nanoelectronics Research Center , Technion , Haifa 320000 , Israel
| |
Collapse
|
26
|
Abstract
An on-chip optical power splitter is a key component of photonic signal processing and quantum integrated circuits and requires compactness, wideband, low insertion loss, and variable splitting ratio. However, designing an on-chip splitter with both customizable splitting ratio and wavelength independence is a big challenge. Here, we propose a tailorable and broadband optical power splitter over 100 nm with low insertion loss less than 0.3%, as well as a compact footprint, based on 1×2 interleaved tapered waveguides. The proposed scheme can design the output power ratio of transverse electric modes, lithographically, and a selection equation of a power splitting ratio is extracted to obtain the desired power ratio. Our splitter scheme is close to an impeccable on-chip optical power splitter for classical and quantum integrated photonic circuits.
Collapse
|
27
|
Zhu W, Wang J, An J, Jiang J, Liu T. The development of a multi-parameter heterogeneous fiber sensor network based on fiber Bragg grating and Fabry-Perot. THE REVIEW OF SCIENTIFIC INSTRUMENTS 2019; 90:046107. [PMID: 31042986 DOI: 10.1063/1.5083684] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/30/2018] [Accepted: 04/02/2019] [Indexed: 06/09/2023]
Abstract
This paper proposes a heterogeneous structure of multiparameter optical fiber sensor network, which is composed of the quasidistributed temperature and strain sensor networks and the discrete pressure and vibration sensor networks. This network can multiplex different types of optical fiber sensors and can automatically identify the subnet type of the access network. We designed two structures of light source distribution and compared their advantages and disadvantages. The sensor network proposed in this paper provides a deliberate exploration for the construction of a large-capacity, large-scale, multiparameter, high-precision optical fiber sensor network.
Collapse
Affiliation(s)
- Wanshan Zhu
- College of Precision Instrument and Optoelectronics Engineering, Tianjin University, Tianjin 300072, China
| | - Jin Wang
- College of Precision Instrument and Optoelectronics Engineering, Tianjin University, Tianjin 300072, China
| | - Jianchang An
- College of Precision Instrument and Optoelectronics Engineering, Tianjin University, Tianjin 300072, China
| | - Junfeng Jiang
- College of Precision Instrument and Optoelectronics Engineering, Tianjin University, Tianjin 300072, China
| | - Tiegen Liu
- College of Precision Instrument and Optoelectronics Engineering, Tianjin University, Tianjin 300072, China
| |
Collapse
|
28
|
Ahmed ANR, Shi S, Zablocki M, Yao P, Prather DW. Tunable hybrid silicon nitride and thin-film lithium niobate electro-optic microresonator. OPTICS LETTERS 2019; 44:618-621. [PMID: 30702693 DOI: 10.1364/ol.44.000618] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/14/2023]
Abstract
This Letter presents, to the best of our knowledge, the first hybrid Si3N4-LiNbO3-based tunable microring resonator where the waveguide is formed by loading a Si3N4 strip on an electro-optic (EO) material of X-cut thin-film LiNbO3. The developed hybrid Si3N4-LiNbO3 microring exhibits a high intrinsic quality factor of 1.85×105, with a ring propagation loss of 0.32 dB/cm, resulting in a spectral linewidth of 13 pm, and a resonance extinction ratio of ∼27 dB within the optical C-band for the transverse electric mode. Using the EO effect of LiNbO3, a 1.78 pm/V resonance tunability near 1550 nm wavelength is demonstrated.
Collapse
|
29
|
Liu D, Zhang C, Liang D, Dai D. Submicron-resonator-based add-drop optical filter with an ultra-large free spectral range. OPTICS EXPRESS 2019; 27:416-422. [PMID: 30696128 DOI: 10.1364/oe.27.000416] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/25/2018] [Accepted: 12/09/2018] [Indexed: 06/09/2023]
Abstract
A low-loss add-drop microring resonator (MRR) with an ultra-large free spectral range (FSR) is demonstrated by introducing an ultra-sharp multimode waveguide bend and bent asymmetrical directional couplers (ADCs). The multimode microring waveguide is introduced to achieve a low bent loss, even with a small radius (e.g., R = 0.8 μm). The bent ADCs are used to suppress the resonance of higher-order modes. For the fabricated device, the transmission at the drop port has a narrow 3 dB-bandwidth of 0.8 nm and a low excess loss of 1.8 dB. A record large FSR of 93 nm is achieved to the best of our knowledge.
Collapse
|
30
|
Abstract
Astrophotonics is the application of photonic technologies to channel, manipulate, and disperse light from one or more telescopes to achieve scientific objectives in astronomy in an efficient and cost-effective way. Utilizing photonic advantage for astronomical spectroscopy is a promising approach to miniaturizing the next generation of spectrometers for large telescopes. It can be primarily attained by leveraging the two-dimensional nature of photonic structures on a chip or a set of fibers, thus reducing the size of spectroscopic instrumentation to a few centimeters and the weight to a few hundred grams. A wide variety of astrophotonic spectrometers is currently being developed, including arrayed waveguide gratings (AWGs), photonic echelle gratings (PEGs), and Fourier-transform spectrometer (FTS). These astrophotonic devices are flexible, cheaper to mass produce, easier to control, and much less susceptible to vibrations and flexure than conventional astronomical spectrographs. The applications of these spectrographs range from astronomy to biomedical analysis. This paper provides a brief review of this new class of astronomical spectrographs.
Collapse
|
31
|
Dong B, Hu T, Luo X, Chang Y, Guo X, Wang H, Kwong DL, Lo GQ, Lee C. Wavelength-Flattened Directional Coupler Based Mid-Infrared Chemical Sensor Using Bragg Wavelength in Subwavelength Grating Structure. NANOMATERIALS (BASEL, SWITZERLAND) 2018; 8:E893. [PMID: 30388814 PMCID: PMC6266145 DOI: 10.3390/nano8110893] [Citation(s) in RCA: 37] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 10/08/2018] [Revised: 10/17/2018] [Accepted: 10/23/2018] [Indexed: 02/06/2023]
Abstract
In this paper, we report a compact wavelength-flattened directional coupler (WFDC) based chemical sensor featuring an incorporated subwavelength grating (SWG) structure for the mid-infrared (MIR). By incorporating a SWG structure into directional coupler (DC), the dispersion in DC can be engineered to allow broadband operation which is advantageous to extract spectroscopic information for MIR sensing analysis. Meanwhile, the Bragg reflection introduced by the SWG structure produces a sharp trough at the Bragg wavelength. This sharp trough is sensitive to the surrounding refractive index (RI) change caused by the existence of analytes. Therefore, high sensitivity can be achieved in a small footprint. Around fivefold enhancement in the operation bandwidth compared to conventional DC is achieved for 100% coupling efficiency in a 40 µm long WFDC experimentally. Detection of dichloromethane (CH₂Cl₂) in ethanol (C₂H₅OH) is investigated in a SWG-based WFDC sensor 136.8 µm long. Sensing performance is studied by 3D finite-difference time domain (FDTD) simulation while sensitivity is derived by computation. Both RI sensing and absorption sensing are examined. RI sensing reveals a sensitivity of -0.47% self-normalized transmitted power change per percentage of CH₂Cl₂ concentration while 0.12% change in the normalized total integrated output power is realized in the absorption sensing. As the first demonstration of the DC based sensor in the MIR, our device has the potential for tertiary mixture sensing by utilizing both changes in the real and imaginary part of RI. It can also be used as a broadband building block for MIR application such as spectroscopic sensing system.
Collapse
Affiliation(s)
- Bowei Dong
- Department of Electrical and Computer Engineering, National University of Singapore, Singapore 117576, Singapore.
- Institute of Microelectronics, Agency for Science, Technology and Research (A*STAR), Singapore 138634, Singapore.
- Center for Intelligent Sensors and MEMS (CISM), National University of Singapore, Singapore 117576, Singapore.
- Graduate School for Integrative Science and Engineering, National University of Singapore, Singapore 117456, Singapore.
| | - Ting Hu
- Institute of Microelectronics, Agency for Science, Technology and Research (A*STAR), Singapore 138634, Singapore.
| | - Xianshu Luo
- Institute of Microelectronics, Agency for Science, Technology and Research (A*STAR), Singapore 138634, Singapore.
| | - Yuhua Chang
- Department of Electrical and Computer Engineering, National University of Singapore, Singapore 117576, Singapore.
- Center for Intelligent Sensors and MEMS (CISM), National University of Singapore, Singapore 117576, Singapore.
| | - Xin Guo
- School of Electrical & Electronic Engineering, Nanyang Technological University, Singapore 639798, Singapore.
| | - Hong Wang
- School of Electrical & Electronic Engineering, Nanyang Technological University, Singapore 639798, Singapore.
| | - Dim-Lee Kwong
- Institute of Microelectronics, Agency for Science, Technology and Research (A*STAR), Singapore 138634, Singapore.
| | - Guo-Qiang Lo
- Institute of Microelectronics, Agency for Science, Technology and Research (A*STAR), Singapore 138634, Singapore.
| | - Chengkuo Lee
- Department of Electrical and Computer Engineering, National University of Singapore, Singapore 117576, Singapore.
- Center for Intelligent Sensors and MEMS (CISM), National University of Singapore, Singapore 117576, Singapore.
- Graduate School for Integrative Science and Engineering, National University of Singapore, Singapore 117456, Singapore.
| |
Collapse
|
32
|
Ying Z, Zhao Z, Feng C, Mital R, Dhar S, Pan DZ, Soref R, Chen RT. Automated logic synthesis for electro-optic logic-based integrated optical computing. OPTICS EXPRESS 2018; 26:28002-28012. [PMID: 30469856 DOI: 10.1364/oe.26.028002] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/11/2018] [Accepted: 09/20/2018] [Indexed: 06/09/2023]
Abstract
Integrated optical computing attracts increasing interest recently as Moore's law approaches the physical limitation. Among all the approaches of integrated optical computing, directed logic that takes the full advantage of integrated photonics and electronics has received lots of investigation since its first introduction in 2007. Meanwhile, as integrated photonics matures, it has become critical to develop automated methods for synthesizing optical devices for large-scale optical designs. In this paper, we propose a general electro-optic (EO) logic in a higher level to explore its potential in integrated computing. Compared to the directed logic, the EO logic leads to a briefer design with shorter optical paths and fewer components. Then a comprehensive gate library based on EO logic is summarized. At last, an And-Inverter Graphs (AIGs) based automated logic synthesis algorithm is described as an example to implement the EO logic, which offers an instruction for the design automation of high-speed integrated optical computing circuits.
Collapse
|
33
|
Han HL, Li H, Zhang XP, Liu A, Lin TY, Chen Z, Lv HB, Lu MH, Liu XP, Chen YF. High performance ultra-compact SOI waveguide crossing. OPTICS EXPRESS 2018; 26:25602-25610. [PMID: 30469659 DOI: 10.1364/oe.26.025602] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/05/2018] [Accepted: 09/03/2018] [Indexed: 06/09/2023]
Abstract
Waveguide crossing is an important integrated photonic component that will be routinely used for high-density and large-scale photonic integrated circuits, such as optical switches and routers. Several techniques have been reported in achieving high performance waveguide crossings on a silicon-on-insulator photonic platform, i.e., low-loss and low-crosstalk waveguide crossings based on multimode interference, bi-layer tapering, optical transformation, metamaterials, and subwavelength gratings. Until recently, not much attention has been given to the reduction of the footprint of waveguide crossings. Here we experimentally demonstrate an ultra-compact waveguide crossing on silicon photonic platform with a footprint only ~1 × 1 μm2. Our simulations show that it has a low insertion loss (< 0.175 dB) and low crosstalk (< -37dB) across the whole C-band, while the fabricated one has an insertion loss < 0.28 dB and crosstalk around -30 dB for the C-band.
Collapse
|
34
|
Peng L, Wang K, Yang Y, Chen Y, Wang G, Zhang B, Chen H. Giant Asymmetric Radiation from an Ultrathin Bianisotropic Metamaterial. ADVANCED SCIENCE (WEINHEIM, BADEN-WURTTEMBERG, GERMANY) 2018; 5:1700922. [PMID: 30027031 PMCID: PMC6051404 DOI: 10.1002/advs.201700922] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 11/24/2017] [Revised: 02/19/2018] [Indexed: 06/08/2023]
Abstract
Unidirectional radiation is of particular interest in high-power lasing and optics. Commonly, however, it is difficult to achieve a unidirectional profile in such a system without breaking reciprocity. Recently, assisted by metamaterials without structural symmetry, antennas that radiate asymmetrically have been developed, hence providing the possibility of achieving unidirectionality. Nevertheless, it has been challenging to achieve extremely high radiation asymmetry in such antennas. Here, it is demonstrated that this radiation asymmetry is further enhanced when magnetic plasmons are present in the metamaterials. Experimentally, it is shown that a thin metamaterial with a thickness of ≈λ0/8 can exhibit a forward-to-backward emission asymmetry of up to 1:32 without any optimization. The work paves the way for manipulating asymmetric radiation by means of metamaterials and may have a variety of promising applications, such as directional optical and quantum emitters, lasers, and absorbers.
Collapse
Affiliation(s)
- Liang Peng
- Key Laboratory for RF Circuits and SystemsHangzhou Dianzi UniversityMinistry of EducationHangzhou310018China
| | - Kewen Wang
- Key Laboratory for RF Circuits and SystemsHangzhou Dianzi UniversityMinistry of EducationHangzhou310018China
| | - Yihao Yang
- State Key Laboratory of Modern Optical InstrumentationZhejiang UniversityHangzhou310027China
| | - Yuntian Chen
- School of Optical and Electronic InformationHuazhong University of Science and TechnologyWuhan430074China
| | - Gaofeng Wang
- Key Laboratory for RF Circuits and SystemsHangzhou Dianzi UniversityMinistry of EducationHangzhou310018China
| | - Baile Zhang
- Division of Physics and Applied PhysicsSchool of Physical and Mathematical SciencesNanyang Technological UniversitySingapore637371Singapore
| | - Hongsheng Chen
- State Key Laboratory of Modern Optical InstrumentationZhejiang UniversityHangzhou310027China
| |
Collapse
|
35
|
Amin R, Ma Z, Maiti R, Khan S, Khurgin JB, Dalir H, Sorger VJ. Attojoule-efficient graphene optical modulators. APPLIED OPTICS 2018; 57:D130-D140. [PMID: 30117932 DOI: 10.1364/ao.57.00d130] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/18/2018] [Accepted: 03/27/2018] [Indexed: 05/27/2023]
Abstract
Electro-optic modulation is a technology-relevant function for signal keying, beam steering, or neuromorphic computing through providing the nonlinear activation function of a perceptron. With silicon-based modulators being bulky and inefficient, here we discuss graphene-based devices heterogeneously integrated. This study provides a critical and encompassing discussion of the physics and performance of graphene. We provide a holistic analysis of the underlying physics of modulators including graphene's index tunability, the underlying optical mode, and discuss resulting performance vectors for this novel class of hybrid modulators. Our results show that reducing the modal area and reducing the effective broadening of the active material are key to improving device performance defined by the ratio of energy-bandwidth and footprint. We further show how the waveguide's polarization must be in-plane with graphene, such as given by plasmonic-slot structures, for performance improvements. A high device performance can be obtained by introducing multi- or bi-layer graphene modulator designs. Lastly, we present recent results of a graphene-based hybrid-photon-plasmon modulator on a silicon platform and discuss electron beam lithography treatments for transferred graphene for the relevant Fermi level tuning. Being physically compact, this 100 aJ/bit modulator opens the path towards a novel class of attojoule efficient opto-electronics.
Collapse
|
36
|
Coherent all-optical transistor based on frustrated total internal reflection. Sci Rep 2018; 8:5069. [PMID: 29567968 PMCID: PMC5864731 DOI: 10.1038/s41598-018-23367-6] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/24/2017] [Accepted: 03/06/2018] [Indexed: 12/03/2022] Open
Abstract
This study aims to design an all-optical transistor based on tunneling of light through frustrated total internal reflection. Under total internal reflection, the electromagnetic wave penetrates into the lower index medium. If a medium with high refractive index is placed close to the boundary of the first one, a portion of light leaks into the second medium. The penetrated electromagnetic field distribution can be influenced by another coherent light in the low refractive index medium via interference, leading to light amplification. Upon this technique, we introduce coherent all-optical transistors based on photonic crystal structures. Subsequently, we inspect the shortest pulse which is amplified by the designed system and also its terahertz repetition rate. We will show that such a system can operate in a cascade form. Operating in terahertz range and the amplification efficiency of around 20 are of advantages of this system.
Collapse
|
37
|
Ying Z, Wang Z, Zhao Z, Dhar S, Pan DZ, Soref R, Chen RT. Silicon microdisk-based full adders for optical computing. OPTICS LETTERS 2018; 43:983-986. [PMID: 29489761 DOI: 10.1364/ol.43.000983] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/30/2017] [Accepted: 01/18/2018] [Indexed: 06/08/2023]
Abstract
Due to the projected saturation of Moore's law, as well as the drastically increasing trend of bandwidth with lower power consumption, silicon photonics has emerged as one of the most promising alternatives that has attracted a lasting interest due to the accessibility and maturity of ultra-compact passive and active integrated photonic components. In this Letter, we demonstrate a ripple-carry electro-optic 2-bit full adder using microdisks, which replaces the core part of an electrical full adder by optical counterparts and uses light to carry signals from one bit to the next with high bandwidth and low power consumption per bit. All control signals of the operands are applied simultaneously within each clock cycle. Thus, the severe latency issue that accumulates as the size of the full adder increases can be circumvented, allowing for an improvement in computing speed and a reduction in power consumption. This approach paves the way for future high-speed optical computing systems in the post-Moore's law era.
Collapse
|
38
|
Chang LM, Liu L, Gong YH, Tan MQ, Yu YD, Li ZY. Polarization-independent directional coupler and polarization beam splitter based on asymmetric cross-slot waveguides. APPLIED OPTICS 2018; 57:678-683. [PMID: 29400730 DOI: 10.1364/ao.57.000678] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/25/2017] [Accepted: 12/27/2017] [Indexed: 06/07/2023]
Abstract
The polarization dependence of a directional coupler (DC) based on asymmetric cross-slot waveguides is investigated. Due to structural birefringence, the coupling behaviors of the quasi-TE and quasi-TM modes in the DC vary with the waveguide geometry. A polarization-independent directional coupler (PIDC) and polarization beam splitter (PBS) are proposed by tailoring the ratio of the coupling length for quasi-TE and quasi-TM modes. The simulated results show that the coupling lengths of the designed PIDC and PBS are 8 and 28.25 μm, respectively. Both the PIDC and PBS show an insertion loss (IL) <0.7 dB on a bandwidth over 100 nm. The extinction ratios are ∼20 dB for PIDC and ∼14 dB for PBS. The fabrication-error tolerance of the practical devices is also discussed. In this study, we employ a commercial software tool for finite difference eigenmode and three-dimensional finite difference time domain methods to perform the numerical simulations.
Collapse
|
39
|
Mohammed NA, El Serafy HO. Ultra-sensitive quasi-distributed temperature sensor based on an apodized fiber Bragg grating. APPLIED OPTICS 2018; 57:273-282. [PMID: 29328176 DOI: 10.1364/ao.57.000273] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/06/2017] [Accepted: 12/11/2017] [Indexed: 06/07/2023]
Abstract
This work targets a remarkable quasi-distributed temperature sensor based on an apodized fiber Bragg grating. To achieve this, the mathematical formula for a proposed apodization function is carried out and tested. Then, an optimization parametric process required to achieve the remarkable accuracy that is based on coupled mode theory (CMT) is done. A detailed investigation for the side lobe analysis, which is a primary judgment factor, especially in quasi-distributed configuration, is investigated. A comparison between elite selection of apodization profiles (extracted from related literatures) and the proposed modified-Nuttal profile is carried out covering reflectivity peak, full width half maximum (FWHM), and side lobe analysis. The optimization process concludes that the proposed modified-Nuttal profile with a length (L) of 15 mm and refractive index modulation amplitude (Δn) of 1.4×10-4 is the optimum choice for single-stage and quasi-distributed temperature sensor networks. At previous values, the proposed profile achieves an acceptable reflectivity peak of 10-0.426 dB, acceptable FWHM of 0.0808 nm, lowest side lobe maximum (SL max) of 7.037×10-12 dB, lowest side lobe average (SL avg) of 3.883×10-12 dB, and lowest side lobe suppression ratio (SLSR) of 1.875×10-11 dB. These optimized characteristics lead to an accurate single-stage sensor with a temperature sensitivity of 0.0136 nm/°C. For the quasi-distributed scenario, a noteworthy total isolation of 91 dB is achieved without temperature, and an isolation of 4.83 dB is achieved while applying temperature of 110°C for a five-stage temperature-sensing network. Further investigation is made proving that consistency in choosing the apodization profile in the quasi-distributed network is mandatory. If the consistency condition is violated, the proposed profile still survives with a casualty of side lobe level rise of -73.2070 dB when adding uniform apodization and -46.4823 dB when adding Gaussian apodization to the five-stage modified-Nuttall temperature-sensing network.
Collapse
|
40
|
Kim JH, Aghaeimeibodi S, Richardson CJK, Leavitt RP, Englund D, Waks E. Hybrid Integration of Solid-State Quantum Emitters on a Silicon Photonic Chip. NANO LETTERS 2017; 17:7394-7400. [PMID: 29131963 DOI: 10.1021/acs.nanolett.7b03220] [Citation(s) in RCA: 45] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/28/2023]
Abstract
Scalable quantum photonic systems require efficient single photon sources coupled to integrated photonic devices. Solid-state quantum emitters can generate single photons with high efficiency, while silicon photonic circuits can manipulate them in an integrated device structure. Combining these two material platforms could, therefore, significantly increase the complexity of integrated quantum photonic devices. Here, we demonstrate hybrid integration of solid-state quantum emitters to a silicon photonic device. We develop a pick-and-place technique that can position epitaxially grown InAs/InP quantum dots emitting at telecom wavelengths on a silicon photonic chip deterministically with nanoscale precision. We employ an adiabatic tapering approach to transfer the emission from the quantum dots to the waveguide with high efficiency. We also incorporate an on-chip silicon-photonic beamsplitter to perform a Hanbury-Brown and Twiss measurement. Our approach could enable integration of precharacterized III-V quantum photonic devices into large-scale photonic structures to enable complex devices composed of many emitters and photons.
Collapse
Affiliation(s)
- Je-Hyung Kim
- Department of Electrical and Computer Engineering and Institute for Research in Electronics and Applied Physics, University of Maryland , College Park, Maryland 20742, United States
- Department of Physics, Ulsan National Institute of Science and Technology (UNIST) , Ulsan 44919, Republic of Korea
| | - Shahriar Aghaeimeibodi
- Department of Electrical and Computer Engineering and Institute for Research in Electronics and Applied Physics, University of Maryland , College Park, Maryland 20742, United States
| | | | - Richard P Leavitt
- Laboratory for Physical Sciences, University of Maryland , College Park, Maryland 20740, United States
| | - Dirk Englund
- Department of Electrical Engineering and Computer Science, Massachusetts Institute of Technology , Cambridge, Massachusetts 02139, United States
| | - Edo Waks
- Department of Electrical and Computer Engineering and Institute for Research in Electronics and Applied Physics, University of Maryland , College Park, Maryland 20742, United States
- Joint Quantum Institute, University of Maryland and the National Institute of Standards and Technology , College Park, Maryland 20742, United States
| |
Collapse
|
41
|
Dushaq G, Nayfeh A, Rasras M. Metal-germanium-metal photodetector grown on silicon using low temperature RF-PECVD. OPTICS EXPRESS 2017; 25:32110-32119. [PMID: 29245875 DOI: 10.1364/oe.25.032110] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/27/2017] [Accepted: 12/03/2017] [Indexed: 06/07/2023]
Abstract
In this paper, germanium metal-semiconductor-metal photodetectors (MSM PDs) are fabricated on Si using a low-temperature two-step deposition technique by RF-PECVD. The photodetectors are optimized to effectively suppress the dark current through the insertion of n-type a-Si:H interlayer between the metal/Ge interface. Tuning the Schottky Barrier Height (SBH) by inserting different thickness of the interlayer is investigated. Results revealed that SBH for electrons and holes can effectively be enhanced by 0.3eV and 0.54eV, respectively. Furthermore, the dark-current (IDark) is suppressed significantly by more than four orders of magnitude. The measured IDark is ∼76 nA for an applied reverse bias of 1.0 V. Additionally, the Ge MSMs structure exhibited a photo responsivity of 0.8A/W at that bias. The proposed low-temperature (<550°C) Ge-on-Si MSM PD demonstrates a great potential for high-performance Ge-based photodetectors in monolithically integrated CMOS platform.
Collapse
|
42
|
Patton RJ, Wood MG, Reano RM. Enhanced photoluminescence from ring resonators in hydrogenated amorphous silicon thin films at telecommunications wavelengths. OPTICS LETTERS 2017; 42:4239-4242. [PMID: 29088133 DOI: 10.1364/ol.42.004239] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/01/2017] [Accepted: 09/09/2017] [Indexed: 06/07/2023]
Abstract
We report enhanced photoluminescence in the telecommunications wavelength range in ring resonators patterned in hydrogenated amorphous silicon thin films deposited via low-temperature plasma enhanced chemical vapor deposition. The thin films exhibit broadband photoluminescence that is enhanced by up to 5 dB by the resonant modes of the ring resonators due to the Purcell effect. Ellipsometry measurements of the thin films show a refractive index comparable to crystalline silicon and an extinction coefficient on the order of 0.001 from 1300 nm to 1600 nm wavelengths. The results are promising for chip-scale integrated optical light sources.
Collapse
|
43
|
Fan G, Orobtchouk R, Han B, Li Y, Li H. 8 x 8 wavelength router of optical network on chip. OPTICS EXPRESS 2017; 25:23677-23683. [PMID: 29041319 DOI: 10.1364/oe.25.023677] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/28/2017] [Accepted: 09/12/2017] [Indexed: 06/07/2023]
Abstract
An integrated 8 x 8 wavelength router based on the micro-ring resonators using 2 x 2 multi-interference (MMI) crossing is demonstrated on silicon-on-insulator (SOI) technology, which is manufactured with microelectronics equipment. Experimental results show a free spectral range (FSR) about ~37 nm, an on/off contrast larger than 20 dB, an imbalance among the channels less than 2 dB, a crosstalk of channels smaller than -10 dB, a spacing between close channels about 3.6 ± 0.7 nm and an output efficiency of every channel smaller than 20 dB.
Collapse
|
44
|
Gambini F, Pintus P, Faralli S, Chiesa M, Preve GB, Cerutti I, Andriolli N. Experimental demonstration of a 24-port packaged multi-microring network-on-chip in silicon photonic platform. OPTICS EXPRESS 2017; 25:22004-22016. [PMID: 29041490 DOI: 10.1364/oe.25.022004] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/12/2017] [Accepted: 05/30/2017] [Indexed: 06/07/2023]
Abstract
A 24-port packaged multi-microring optical network-on-chip has been tested for simultaneous co- and counter-propagating transmissions at the same wavelength at 10 Gbps. In the co-propagating scenario communications up to five hops with one interfering signal have been tested, together with transmissions impaired by up to three interfering signals. In the counter-propagating scenario the device performance has been investigated exploiting the ring resonators in both shared-source and shared-destination configurations. The spectral characterization is in good agreement with the theoretical results. Bit-error-rate measurements indicate power penalties at BER=10-9 limited to (i) 0.5 dB in the co-propagating scenarios independently from the number of interfering transmissions, (ii) 0.8 dB in the counter-propagating scenario with shared-source configuration, and (iii) 2 dB in the counter-propagating scenario with shared-destination configuration.
Collapse
|
45
|
García-Meca C, Lechago S, Brimont A, Griol A, Mas S, Sánchez L, Bellieres L, Losilla NS, Martí J. On-chip wireless silicon photonics: from reconfigurable interconnects to lab-on-chip devices. LIGHT, SCIENCE & APPLICATIONS 2017; 6:e17053. [PMID: 30167296 PMCID: PMC6062325 DOI: 10.1038/lsa.2017.53] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/01/2016] [Revised: 03/21/2017] [Accepted: 03/23/2017] [Indexed: 05/20/2023]
Abstract
Photonic integrated circuits are developing as key enabling components for high-performance computing and advanced network-on-chip, as well as other emerging technologies such as lab-on-chip sensors, with relevant applications in areas from medicine and biotechnology to aerospace. These demanding applications will require novel features, such as dynamically reconfigurable light pathways, obtained by properly harnessing on-chip optical radiation. In this paper, we introduce a broadband, high directivity (>150), low loss and reconfigurable silicon photonics nanoantenna that fully enables on-chip radiation control. We propose the use of these nanoantennas as versatile building blocks to develop wireless (unguided) silicon photonic devices, which considerably enhance the range of achievable integrated photonic functionalities. As examples of applications, we demonstrate 160 Gbit s-1 data transmission over mm-scale wireless interconnects, a compact low-crosstalk 12-port crossing and electrically reconfigurable pathways via optical beam steering. Moreover, the realization of a flow micro-cytometer for particle characterization demonstrates the smart system integration potential of our approach as lab-on-chip devices.
Collapse
Affiliation(s)
- Carlos García-Meca
- Nanophotonics Technology Center, Universitat Politècnica de València, 46022 Valencia, Spain
| | - Sergio Lechago
- Nanophotonics Technology Center, Universitat Politècnica de València, 46022 Valencia, Spain
| | - Antoine Brimont
- Nanophotonics Technology Center, Universitat Politècnica de València, 46022 Valencia, Spain
| | - Amadeu Griol
- Nanophotonics Technology Center, Universitat Politècnica de València, 46022 Valencia, Spain
| | - Sara Mas
- Nanophotonics Technology Center, Universitat Politècnica de València, 46022 Valencia, Spain
| | - Luis Sánchez
- Nanophotonics Technology Center, Universitat Politècnica de València, 46022 Valencia, Spain
| | - Laurent Bellieres
- Nanophotonics Technology Center, Universitat Politècnica de València, 46022 Valencia, Spain
| | - Nuria S Losilla
- Nanophotonics Technology Center, Universitat Politècnica de València, 46022 Valencia, Spain
| | - Javier Martí
- Nanophotonics Technology Center, Universitat Politècnica de València, 46022 Valencia, Spain
| |
Collapse
|
46
|
Xu X, Zheng X, He F, Wang Z, Subbaraman H, Wang Y, Jia B, Chen RT. Observation of Third-order Nonlinearities in Graphene Oxide Film at Telecommunication Wavelengths. Sci Rep 2017; 7:9646. [PMID: 28851947 PMCID: PMC5575126 DOI: 10.1038/s41598-017-09583-6] [Citation(s) in RCA: 28] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/19/2017] [Accepted: 07/21/2017] [Indexed: 12/01/2022] Open
Abstract
All-optical switches have been considered as a promising solution to overcome the fundamental speed limit of the current electronic switches. However, the lack of a suitable third-order nonlinear material greatly hinders the development of this technology. Here we report the observation of ultrahigh third-order nonlinearity about 0.45 cm2/GW in graphene oxide thin films at the telecommunication wavelength region, which is four orders of magnitude higher than that of single crystalline silicon. Besides, graphene oxide is water soluble and thus easy to process due to the existence of oxygen containing groups. These unique properties can potentially significantly advance the performance of all-optical switches.
Collapse
Affiliation(s)
- Xiaochuan Xu
- Omega Optics, Inc., 8500 Shoal Creek Blvd., Bldg. 4, Suite 200, Austin, TX, 78757, USA.
| | - Xiaorui Zheng
- Centre for Micro-Photonics, Faculty of Science, Engineering and Technology, Swinburne University of Technology, P. O. Box 218, Hawthorn, VIC, 3122, Australia
| | - Feng He
- Department of Mechanical Engineering, The University of Texas at Austin, Austin, Texas, 78712, USA
| | - Zheng Wang
- Materials Science and Engineering Program, Texas Materials Institute, The University of Texas at Austin, Austin, Texas, 78712, USA
| | - Harish Subbaraman
- Omega Optics, Inc., 8500 Shoal Creek Blvd., Bldg. 4, Suite 200, Austin, TX, 78757, USA.,Department of Electrical and Computer Engineering, Boise State University, Boise, Idaho, 83725, USA
| | - Yaguo Wang
- Department of Mechanical Engineering, The University of Texas at Austin, Austin, Texas, 78712, USA
| | - Baohua Jia
- Centre for Micro-Photonics, Faculty of Science, Engineering and Technology, Swinburne University of Technology, P. O. Box 218, Hawthorn, VIC, 3122, Australia
| | - Ray T Chen
- Omega Optics, Inc., 8500 Shoal Creek Blvd., Bldg. 4, Suite 200, Austin, TX, 78757, USA. .,Department of Electrical and Computer Engineering, The University of Texas at Austin, 10100 Burnet Rd., MER 160, Austin, Texas, 78758, USA.
| |
Collapse
|
47
|
Wang S, Feng X, Gao S, Shi Y, Dai T, Yu H, Tsang HK, Dai D. On-chip reconfigurable optical add-drop multiplexer for hybrid wavelength/mode-division-multiplexing systems. OPTICS LETTERS 2017; 42:2802-2805. [PMID: 28708173 DOI: 10.1364/ol.42.002802] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/25/2017] [Accepted: 06/18/2017] [Indexed: 06/07/2023]
Abstract
A silicon-based on-chip reconfigurable optical add-drop multiplexer (ROADM) is presented for hybrid wavelength-division-multiplexing-mode-division-multiplexing systems. The present ROADM consists of a four-channel mode demultiplexer, four wavelength-selective thermo-optic switches based on microring resonators, and a four-channel mode multiplexer. With the present ROADM, one can add/drop one of wavelength channels of any mode to/from the multimode bus waveguide successfully with an excess loss of 2-5 dB and an extinction ratio of ∼20 dB over a wavelength range of 1525-1555 nm.
Collapse
|
48
|
Gazman A, Browning C, Bahadori M, Zhu Z, Samadi P, Rumley S, Vujicic V, Barry LP, Bergman K. Software-defined control-plane for wavelength selective unicast and multicast of optical data in a silicon photonic platform. OPTICS EXPRESS 2017; 25:232-242. [PMID: 28085816 DOI: 10.1364/oe.25.000232] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/06/2023]
Abstract
We demonstrate a programmable control-plane based on field programmable gate array (FPGA) with a power-efficient algorithm for optical unicast, multicast, and broadcast functionalities in a silicon photonic platform. The platform includes a silicon photonic 1×8 microring array chip which in conjunction with a fast tunable laser over the C-band is capable of delivering software controlled wavelength selective functionality on top of spatial switching. We characterize the thermo-optic response of microring resonators and extract key parameters necessary for the development of the control-plane. The performance of the proposed architecture is tested with 10 Gb/s on-off keying (OOK) optical data and error-free operation is verified for various wavelength and spatial switching scenarios. Lastly, we evaluate electrical power and energy consumption required to reconfigure the silicon photonic device for all possible wavelength operations and output ports combinations and show that unicast, multicast of two, three, four, five, six, seven, and broadcast functions are achieved with energy overheads of 0.02, 0.07, 0.18, 0.49, 0.76, 1.01, 1.3, and 1.55 pJ/bit, respectively.
Collapse
|
49
|
Thubthimthong B, Hane K. All-optical guided resonance tuning in hybrid GaN/Si microring induced by non-radiatively trapped injected hot electrons. OPTICS EXPRESS 2016; 24:29643-29658. [PMID: 28059365 DOI: 10.1364/oe.24.029643] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/06/2023]
Abstract
Advanced Si/III-V nanophotonics that emerged in the last decade has already founded the on-chip optical interconnect technology for future integrated systems on chip. New possibilities of light-on-chip applications beside signal transmissions, such as, all-optical sensing, have been given but small attention. Here, all-optical ultraviolet (UV)-sensitive guided resonance tuning in a hybrid GaN/Si microring resonator (HMR) was studied. Resonance redshifting by free-space UV pumping resulted in a 12 dB guided-mode modulation at the 1560 nm telecommunication wavelength. Investigations by experiments, theory, and simulations indicated the origin of the tuning mechanism from hot-electron heat extraction via defects-assisted non-radiative recombinations and electron-phonon interactions. A photothermal tuning efficiency of 73 pm/mW was attained at a pump power of 850 μW, thank to photothermal energy directly generated in the HMR. The UV-sensitive visible-blind all-optical tuning in the HMR may benefit all-optical UV sensing for the optical data era to come.
Collapse
|
50
|
Wang S, Wu H, Tsang HK, Dai D. Monolithically integrated reconfigurable add-drop multiplexer for mode-division-multiplexing systems. OPTICS LETTERS 2016; 41:5298-5301. [PMID: 27842117 DOI: 10.1364/ol.41.005298] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/06/2023]
Abstract
An integrated reconfigurable optical add-drop multiplexer (ROADM) for mode-division-multiplexing systems is proposed and demonstrated for the first time, to the best of our knowledge. The present ROADM with four mode-channels is composed of a four-channel mode demultiplexer, four identical 2×2 thermo-optic Mach-Zehnder switches (MZSs), and a four-channel mode multiplexer, which are integrated monolithically on silicon. All the devices are designed for operation with TM polarization. The ROADM can add/drop any one of the mode channels freely by thermally turning on/off the corresponding MZS. For the added/dropped mode-channels, the excess loss is 1-5 dB, and the extinction ratio is 15-20 dB in the wavelength range of 1535-1565 nm.
Collapse
|