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Liu X, Zhang Z, Zhou J, Liu W, Zhou G, Lee C. Development of Photonic In-Sensor Computing Based on a Mid-Infrared Silicon Waveguide Platform. ACS NANO 2024; 18:22938-22948. [PMID: 39133149 DOI: 10.1021/acsnano.4c04052] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 08/13/2024]
Abstract
Neuromorphic in-sensor computing has provided an energy-efficient solution to smart sensor design and on-chip data processing. In recent years, various free-space-configured optoelectronic chips have been demonstrated for on-chip neuromorphic vision processing. However, on-chip waveguide-based in-sensor computing with different data modalities is still lacking. Here, by integrating a responsivity-tunable graphene photodetector onto the silicon waveguide, an on-chip waveguide-based in-sensor processing unit is realized in the mid-infrared wavelength range. The weighting operation is achieved by dynamically tuning the bias of the photodetector, which could reach 4 bit weighting precision. Three different neural network tasks are performed to demonstrate the capabilities of our device. First, image preprocessing is performed for handwritten digits and fashion product classification as a general task. Next, resistive-type glove sensor signals are reversed and applied to the photodetector as an input for gesture recognition. Finally, spectroscopic data processing for binary gas mixture classification is demonstrated by utilizing the broadband performance of the device from 3.65 to 3.8 μm. By extending the wavelength from near-infrared to mid-infrared, our work shows the capability of a waveguide-integrated tunable graphene photodetector as a viable weighting solution for photonic in-sensor computing. Furthermore, such a solution could be used for large-scale neuromorphic in-sensor computing in photonic integrated circuits at the edge.
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Affiliation(s)
- Xinmiao Liu
- Department of Electrical and Computer Engineering, National University of Singapore, Singapore 117583, Singapore
- Center for Intelligent Sensors and MEMS (CISM), National University of Singapore, Singapore 117608, Singapore
- Department of Mechanical Engineering, National University of Singapore, Singapore 117575, Singapore
| | - Zixuan Zhang
- Department of Electrical and Computer Engineering, National University of Singapore, Singapore 117583, Singapore
- Center for Intelligent Sensors and MEMS (CISM), National University of Singapore, Singapore 117608, Singapore
| | - Jingkai Zhou
- Department of Electrical and Computer Engineering, National University of Singapore, Singapore 117583, Singapore
- Center for Intelligent Sensors and MEMS (CISM), National University of Singapore, Singapore 117608, Singapore
| | - Weixin Liu
- Department of Electrical and Computer Engineering, National University of Singapore, Singapore 117583, Singapore
- Center for Intelligent Sensors and MEMS (CISM), National University of Singapore, Singapore 117608, Singapore
| | - Guangya Zhou
- Center for Intelligent Sensors and MEMS (CISM), National University of Singapore, Singapore 117608, Singapore
- Department of Mechanical Engineering, National University of Singapore, Singapore 117575, Singapore
| | - Chengkuo Lee
- Department of Electrical and Computer Engineering, National University of Singapore, Singapore 117583, Singapore
- Center for Intelligent Sensors and MEMS (CISM), National University of Singapore, Singapore 117608, Singapore
- NUS Suzhou Research Institute (NUSRI), Suzhou, Jiangsu 215123, China
- NUS Graduate School's Integrative Sciences and Engineering Programme (ISEP), National University of Singapore, Singapore 117583, Singapore
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2
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Liu Y, Xia L, Li T, Sun Y, Zhou P, Shen L, Zou Y. High-efficiency mid-infrared on-chip silicon grating couplers for perfectly vertical coupling. OPTICS LETTERS 2023; 48:239-242. [PMID: 36638427 DOI: 10.1364/ol.478751] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/18/2022] [Accepted: 12/07/2022] [Indexed: 06/17/2023]
Abstract
We present, to our knowledge, the first experimental demonstration of two on-chip gratings for perfectly vertical coupling at wavelengths of 3350 nm and 3550 nm, respectively. An anti-backreflection unit containing a fully etched trench and a subwavelength pillar is introduced in each grating period, together with a binary-approximated blazed unit, interleaving fully and shallow-etched slots in 500-nm thick silicon film. Both gratings show a strong ability to eliminate backreflection and provide predicted directionality of around 80%. The physical theoretical analysis is applied during further apodization for mitigating the computation of the optimization algorithm, improving the efficiency and optimization reliability, and increasing the fabrication robustness. The measured coupling efficiencies (CEs) of the gratings are -5.58 dB and -4.34 dB at wavelengths of 3350 nm and 3550 nm, with a 3-dB bandwidth of at least 87 nm and 210 nm, respectively.
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3
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Beliaev LY, Stounbjerg PG, Finco G, Bunea AI, Malureanu R, Lindvold LR, Takayama O, Andersen PE, Lavrinenko AV. Pedestal High-Contrast Gratings for Biosensing. NANOMATERIALS 2022; 12:nano12101748. [PMID: 35630973 PMCID: PMC9145707 DOI: 10.3390/nano12101748] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 04/15/2022] [Revised: 05/09/2022] [Accepted: 05/17/2022] [Indexed: 12/04/2022]
Abstract
High-contrast gratings (HCG) are an excellent candidate for label-free detection of various kinds of biomarkers because they exhibit sharp and sensitive optical resonances. In this work, we experimentally show the performance of pedestal HCG (PHCG), which is significantly enhanced in comparison with that of conventional HCG. PCHGs were found to provide a 11.2% improvement in bulk refractive index sensitivity, from 482 nm/RIU for the conventional design to 536 nm/RIU. The observed resonance was narrower, resulting in a higher Q-factor and figure of merit. By depositing Al2O3, HfO2, and TiO2 of different thicknesses as model analyte layers, surface sensitivity values were estimated to be 10.5% better for PHCG. To evaluate the operation of the sensor in solution, avidin was employed as a model analyte. For avidin detection, the surface of the HCG was first silanized and subsequently functionalized with biotin, which is well known for its ability to bind selectively to avidin. A consistent red shift was observed with the addition of each of the functional layers, and the analysis of the spectral shift for various concentrations of avidin made it possible to calculate the limit of detection (LoD) and limit of quantification (LoQ) for the structures. PHCG showed a LoD of 2.1 ng/mL and LoQ of 85 ng/mL, significantly better than the values 3.2 ng/mL and 213 ng/mL respectively, obtained with the conventional HCG. These results demonstrate that the proposed PHCG have great potential for biosensing applications, particularly for detecting and quantifying low analyte concentrations.
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Affiliation(s)
- Leonid Yu. Beliaev
- DTU Fotonik–Department of Photonics Engineering, Technical University of Denmark, Ørsteds Plads, Building 345A, DK-2800 Kongens Lyngby, Denmark; (G.F.); (R.M.); (O.T.); (A.V.L.)
- Correspondence:
| | - Peter Groth Stounbjerg
- DTU Health–Department of Health Technology, Technical University of Denmark, Ørsteds Plads, Building 345C, DK-2800 Kongens Lyngby, Denmark; (P.G.S.); (L.R.L.); (P.E.A.)
| | - Giovanni Finco
- DTU Fotonik–Department of Photonics Engineering, Technical University of Denmark, Ørsteds Plads, Building 345A, DK-2800 Kongens Lyngby, Denmark; (G.F.); (R.M.); (O.T.); (A.V.L.)
- Optical Nanomaterial Group, Department of Physics, Institute for Quantum Electronics, ETH Zürich, Auguste-Piccard-Hof 1, HPT D5, 8093 Zürich, Switzerland
| | - Ada-Ioana Bunea
- DTU Nanolab–National Centre for Nano Fabrication and Characterization, Technical University of Denmark, Ørsteds Plads, Building 347, DK-2800 Kongens Lyngby, Denmark;
| | - Radu Malureanu
- DTU Fotonik–Department of Photonics Engineering, Technical University of Denmark, Ørsteds Plads, Building 345A, DK-2800 Kongens Lyngby, Denmark; (G.F.); (R.M.); (O.T.); (A.V.L.)
| | - Lars René Lindvold
- DTU Health–Department of Health Technology, Technical University of Denmark, Ørsteds Plads, Building 345C, DK-2800 Kongens Lyngby, Denmark; (P.G.S.); (L.R.L.); (P.E.A.)
| | - Osamu Takayama
- DTU Fotonik–Department of Photonics Engineering, Technical University of Denmark, Ørsteds Plads, Building 345A, DK-2800 Kongens Lyngby, Denmark; (G.F.); (R.M.); (O.T.); (A.V.L.)
| | - Peter E. Andersen
- DTU Health–Department of Health Technology, Technical University of Denmark, Ørsteds Plads, Building 345C, DK-2800 Kongens Lyngby, Denmark; (P.G.S.); (L.R.L.); (P.E.A.)
| | - Andrei V. Lavrinenko
- DTU Fotonik–Department of Photonics Engineering, Technical University of Denmark, Ørsteds Plads, Building 345A, DK-2800 Kongens Lyngby, Denmark; (G.F.); (R.M.); (O.T.); (A.V.L.)
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Detection of volatile organic compounds using mid-infrared silicon nitride waveguide sensors. Sci Rep 2022; 12:5572. [PMID: 35368033 PMCID: PMC8976853 DOI: 10.1038/s41598-022-09597-9] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/04/2021] [Accepted: 03/15/2022] [Indexed: 11/29/2022] Open
Abstract
Mid-infrared (mid-IR) sensors consisting of silicon nitride (SiN) waveguides were designed and tested to detect volatile organic compounds (VOCs). SiN thin films, prepared by low-pressure chemical vapor deposition (LPCVD), have a broad mid-IR transparent region and a lower refractive index (nSiN = 2.0) than conventional materials such as Si (nSi = 3.4), which leads to a stronger evanescent wave and therefore higher sensitivity, as confirmed by a finite-difference eigenmode (FDE) calculation. Further, in-situ monitoring of three VOCs (acetone, ethanol, and isoprene) was experimentally demonstrated through characteristic absorption measurements at wavelengths λ = 3.0–3.6 μm. The SiN waveguide showed a five-fold sensitivity improvement over the Si waveguide due to its stronger evanescent field. To our knowledge, this is the first time SiN waveguides are used to perform on-chip mid-IR spectral measurements for VOC detection. Thus, the developed waveguide sensor has the potential to be used as a compact device module capable of monitoring multiple gaseous analytes for health, agricultural and environmental applications.
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Stirling CJ, Halir R, Sánchez-Postigo A, Qu Z, Reynolds JD, Penadés JS, Senthil Murugan G, Ortega-Moñux A, Wangüemert-Pérez JG, Molina-Fernández Í, Mashanovich GZ, Nedeljkovic M. Broadband 2 × 2 multimode interference coupler for mid-infrared wavelengths. OPTICS LETTERS 2021; 46:5300-5303. [PMID: 34724460 DOI: 10.1364/ol.439985] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/13/2021] [Accepted: 09/25/2021] [Indexed: 06/13/2023]
Abstract
Beam splitters are core components of photonic integrated circuits and are often implemented with multimode interference couplers. While these devices offer high performance, their operational bandwidth is still restrictive for sensing applications in the mid-infrared wavelength range. Here we experimentally demonstrate a subwavelength-structured 2×2 multimode interference coupler with high performance in the 3.1-3.7µm range, doubling the bandwidth of a conventional device.
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Alberti S, Datta A, Jágerská J. Integrated Nanophotonic Waveguide-Based Devices for IR and Raman Gas Spectroscopy. SENSORS (BASEL, SWITZERLAND) 2021; 21:7224. [PMID: 34770531 PMCID: PMC8587819 DOI: 10.3390/s21217224] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 09/17/2021] [Revised: 10/25/2021] [Accepted: 10/26/2021] [Indexed: 11/17/2022]
Abstract
On-chip devices for absorption spectroscopy and Raman spectroscopy have been developing rapidly in the last few years, triggered by the growing availability of compact and affordable tunable lasers, detectors, and on-chip spectrometers. Material processing that is compatible with mass production has been proven to be capable of long low-loss waveguides of sophisticated designs, which are indispensable for high-light-analyte interactions. Sensitivity and selectivity have been further improved by the development of sorbent cladding. In this review, we discuss the latest advances and challenges in the field of waveguide-enhanced Raman spectroscopy (WERS) and waveguide infrared absorption spectroscopy (WIRAS). The development of integrated light sources and detectors toward miniaturization will be presented, together with the recent advances on waveguides and cladding to improve sensitivity. The latest reports on gas-sensing applications and main configurations for WERS and WIRAS will be described, and the most relevant figures of merit and limitations of different sensor realizations summarized.
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Affiliation(s)
- Sebastián Alberti
- Department of Physics and Technology, UiT the Arctic University of Norway, 9019 Tromsø, Norway; (A.D.); (J.J.)
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7
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Yin S, Wang X, Wang Z, Xiao S, Guan X. Silicon Photonic Polarization Multiplexing Sensor with Both Large Range and High Resolution. SENSORS (BASEL, SWITZERLAND) 2020; 20:s20205870. [PMID: 33081374 PMCID: PMC7589641 DOI: 10.3390/s20205870] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 09/23/2020] [Revised: 10/14/2020] [Accepted: 10/14/2020] [Indexed: 06/11/2023]
Abstract
A silicon photonic polarization multiplexing (PM) sensor featuring both a large range and a high resolution is proposed and experimentally demonstrated. The sensor includes a Fabry-Pérot (FP) resonator and a microring resonator (MRR) functioning as the sensing parts. With PM technology, the FP resonator only works on the transverse-electric mode while the MRR only on the transverse-magnetic mode. Thus, the proposed sensor can simultaneously achieve a large range with a short FP resonator and a high resolution with a high-Q MRR. Measured results show a range of 113 °C and a resolution of 0.06 °C for temperature sensing, and a range of 0.58 RIU (refractive index unit) with the resolution of 0.002 RIU for analyte refractive index sensing.
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Affiliation(s)
- Shaojie Yin
- School of Electrical Engineering, Yanshan University, Qinhuangdao 066004, China; (S.Y.); (Z.W.)
| | - Xiaoyan Wang
- Institute for Future, Qingdao University, Qingdao 266071, China;
| | - Zhibin Wang
- School of Electrical Engineering, Yanshan University, Qinhuangdao 066004, China; (S.Y.); (Z.W.)
| | - Sanshui Xiao
- DTU Fotonik, Department of Photonics Engineering, Technical University of Denmark, Ørsteds Plads, Building 345A, 2800 Kgs. Lyngby, Denmark;
| | - Xiaowei Guan
- DTU Fotonik, Department of Photonics Engineering, Technical University of Denmark, Ørsteds Plads, Building 345A, 2800 Kgs. Lyngby, Denmark;
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8
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Mittal V, Mashanovich GZ, Wilkinson JS. Perspective on Thin Film Waveguides for on-Chip Mid-Infrared Spectroscopy of Liquid Biochemical Analytes. Anal Chem 2020; 92:10891-10901. [PMID: 32658466 DOI: 10.1021/acs.analchem.0c01296] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/21/2023]
Abstract
Miniaturized spectrometers offering low cost, low reagent consumption, high throughput, sensitivity and automation are the future of sensing and have significant applications in environmental monitoring, food safety, biotechnology, pharmaceuticals, and healthcare. Midinfrared (MIR) spectroscopy employing complementary metal oxide semiconductor (CMOS) compatible thin film waveguides and microfluidics shows great promise toward highly integrated and robust detection tools and liquid handling. This perspective provides an overview of the emergence of thin film optical waveguides used for evanescent field sensing of liquid chemical and biological samples for MIR absorption spectroscopy. The state of the art of new material and waveguide systems used for spectroscopic measurements in the MIR is presented. An outlook on the advantages and future of waveguide-based MIR spectroscopy for application in clinical settings for point-of-care biochemical analysis is discussed.
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Affiliation(s)
- Vinita Mittal
- Zepler Institute for Photonics and Nanoelectronics, University of Southampton, Southampton, SO17 1BJ, United Kingdom
| | - Goran Z Mashanovich
- Zepler Institute for Photonics and Nanoelectronics, University of Southampton, Southampton, SO17 1BJ, United Kingdom.,School of Electrical Engineering, University of Belgrade, 11120 Belgrade, Serbia
| | - James S Wilkinson
- Zepler Institute for Photonics and Nanoelectronics, University of Southampton, Southampton, SO17 1BJ, United Kingdom
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9
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Ma Y, Dong B, Lee C. Progress of infrared guided-wave nanophotonic sensors and devices. NANO CONVERGENCE 2020; 7:12. [PMID: 32239361 PMCID: PMC7113365 DOI: 10.1186/s40580-020-00222-x] [Citation(s) in RCA: 31] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/24/2019] [Accepted: 03/12/2020] [Indexed: 06/01/2023]
Abstract
Nanophotonics, manipulating light-matter interactions at the nanoscale, is an appealing technology for diversified biochemical and physical sensing applications. Guided-wave nanophotonics paves the way to miniaturize the sensors and realize on-chip integration of various photonic components, so as to realize chip-scale sensing systems for the future realization of the Internet of Things which requires the deployment of numerous sensor nodes. Starting from the popular CMOS-compatible silicon nanophotonics in the infrared, many infrared guided-wave nanophotonic sensors have been developed, showing the advantages of high sensitivity, low limit of detection, low crosstalk, strong detection multiplexing capability, immunity to electromagnetic interference, small footprint and low cost. In this review, we provide an overview of the recent progress of research on infrared guided-wave nanophotonic sensors. The sensor configurations, sensing mechanisms, sensing performances, performance improvement strategies, and system integrations are described. Future development directions are also proposed to overcome current technological obstacles toward industrialization.
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Affiliation(s)
- Yiming Ma
- 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, 117608 Singapore
- NUS Suzhou Research Institute (NUSRI), Suzhou Industrial Park, Suzhou, 215123 China
| | - Bowei Dong
- 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, 117608 Singapore
- NUS Graduate School for Integrative Science and Engineering (NGS), National University of Singapore, Singapore, 117456 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, 117608 Singapore
- NUS Suzhou Research Institute (NUSRI), Suzhou Industrial Park, Suzhou, 215123 China
- NUS Graduate School for Integrative Science and Engineering (NGS), National University of Singapore, Singapore, 117456 Singapore
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10
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Chang Y, Dong B, Ma Y, Wei J, Ren Z, Lee C. Vernier effect-based tunable mid-infrared sensor using silicon-on-insulator cascaded rings. OPTICS EXPRESS 2020; 28:6251-6260. [PMID: 32225878 DOI: 10.1364/oe.382226] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/04/2019] [Accepted: 01/15/2020] [Indexed: 06/10/2023]
Abstract
Vernier effect has been captivated as a promising approach to achieve high-performance photonic sensors. However, experimental demonstration of such sensors in mid-infrared (MIR) range, which covers abundant absorption fingerprints of molecules, is still lacking. Here, we report Vernier effect-based thermally tunable photonic sensors using cascaded ring resonators fabricated on the silicon-on-insulator (SOI) platform. The radii and the coupling gaps in two rings are investigated as key design parameters. By applying organic liquids on our device, we observe an envelope shift of 48 nm with a sensitivity of 3000 nm/RIU and an intensity drop of 6.7 dB. Besides, our device can be thermally tuned with a sensitivity of 0.091 nm/mW. Leveraging the characteristic molecular absorption in the MIR, our work offers new possibilities for complex index sensing, which has wide applications in on-chip photonic sensors.
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Chang CW, Xu X, Chakravarty S, Huang HC, Tu LW, Chen QY, Dalir H, Krainak MA, Chen RT. Pedestal subwavelength grating metamaterial waveguide ring resonator for ultra-sensitive label-free biosensing. Biosens Bioelectron 2019; 141:111396. [PMID: 31195197 DOI: 10.1016/j.bios.2019.111396] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/25/2019] [Revised: 05/23/2019] [Accepted: 05/31/2019] [Indexed: 12/11/2022]
Abstract
Mode volume overlap factor is one of the parameters determining the sensitivity of a sensor. In past decades, many approaches have been proposed to increase the mode volume overlap. As the increased mode volume overlap factor results in reduced mode confinement, the maximum value is ultimately determined by the micro- and nano-structure of the refractive index distribution of the sensing devices. Due to the asymmetric index profile along the vertical direction on silicon-on-insulator platform, further increasing the sensitivity of subwavelength grating metamaterial (SGM) waveguide based sensors is challenging. In this paper, we propose and demonstrate pedestaled SGM which reduces the asymmetricity and thus allows further increasing the interaction between optical field and analytes. The pedestal structure can be readily formed by a controlled undercut etching. Both theoretical analysis and experimental demonstration show a significant improvement of sensitivity. The bulk sensitivity and surface sensitivity are improved by 28.8% and 1000 times, respectively. The detection of streptavidin at a low concentration of 0.1 ng/mL (∼1.67 pM) is also demonstrated through real-time monitoring of the resonance shift. A ∼400 fM streptavidin limit of detection is expected with a 0.01nm resolution spectrum analyzer based on the real-time measurement of streptavidin detection results from two-site binding model fitting.
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Affiliation(s)
- Ching-Wen Chang
- Department of Electrical and Computer Engineering, The University of Texas at Austin, Austin, TX, 78758, USA; Department of Physics and Center of Crystal Research, National Sun Yat-sen University, Kaohsiung, 80424, Taiwan, ROC
| | - Xiaochuan Xu
- Department of Electrical and Computer Engineering, The University of Texas at Austin, Austin, TX, 78758, USA; Omega Optics Inc, 8500 Shoal Creek Blvd, Austin, TX, 78759, USA.
| | - Swapnajit Chakravarty
- Department of Electrical and Computer Engineering, The University of Texas at Austin, Austin, TX, 78758, USA; Omega Optics Inc, 8500 Shoal Creek Blvd, Austin, TX, 78759, USA
| | - Hui-Chun Huang
- Department of Materials and Optoelectronic Science, National Sun Yat-sen University, Kaohsiung, 80424, Taiwan, ROC
| | - Li-Wei Tu
- Department of Physics and Center of Crystal Research, National Sun Yat-sen University, Kaohsiung, 80424, Taiwan, ROC; Department of Medical Laboratory Science and Biotechnology, Kaohsiung Medical University, Kaohsiung, 80708, Taiwan, ROC
| | - Quark Yungsung Chen
- Department of Physics and Center of Crystal Research, National Sun Yat-sen University, Kaohsiung, 80424, Taiwan, ROC
| | - Hamed Dalir
- Department of Electrical and Computer Engineering, The University of Texas at Austin, Austin, TX, 78758, USA; Omega Optics Inc, 8500 Shoal Creek Blvd, Austin, TX, 78759, USA
| | | | - Ray T Chen
- Department of Electrical and Computer Engineering, The University of Texas at Austin, Austin, TX, 78758, USA; Omega Optics Inc, 8500 Shoal Creek Blvd, Austin, TX, 78759, USA.
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Ramirez JM, Liu Q, Vakarin V, Le Roux X, Frigerio J, Ballabio A, Alonso-Ramos C, Simola ET, Vivien L, Isella G, Marris-Morini D. Broadband integrated racetrack ring resonators for long-wave infrared photonics. OPTICS LETTERS 2019; 44:407-410. [PMID: 30644912 DOI: 10.1364/ol.44.000407] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/30/2018] [Accepted: 12/13/2018] [Indexed: 06/09/2023]
Abstract
Long-wave infrared photonics is an exciting research field meant to revolutionize our daily life by means of key advances in several domains including communications, imaging systems, medical care, environmental monitoring, or multispectral chemical sensing, among others. For this purpose, integrated photonics is particularly promising owing to its compactness, mass fabrication, and energy-efficient characteristics. We present in this Letter, for the first time to the best of our knowledge, broadband integrated racetrack ring resonators operating within the crucial molecular fingerprint region. Devices show an operation bandwidth of Δλ≈900 nm with a central wavelength of λ≈8 μm, a quality factor of Q≈3200, and an extinction ratio of ER≈10 dB around the critical coupling condition. These resonant structures establish the basis of a new generation of integrated building blocks for long-wave infrared photonics that opens the route towards miniaturized multitarget molecule detection systems.
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13
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Chen N, Dong B, Luo X, Wang H, Singh N, Lo GQ, Lee C. Efficient and broadband subwavelength grating coupler for 3.7 μm mid-infrared silicon photonics integration. OPTICS EXPRESS 2018; 26:26242-26256. [PMID: 30469715 DOI: 10.1364/oe.26.026242] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/07/2018] [Accepted: 08/02/2018] [Indexed: 06/09/2023]
Abstract
A grating coupler is an essential building block for compact and flexible photonics integration. In order to meet the increasing demand of mid-infrared (MIR) integrated photonics for sensitive chemical/gas sensing, we report a silicon-on-insulator (SOI) based MIR subwavelength grating coupler (SWGC) operating in the 3.7 μm wavelength range. We provide the design guidelines of a uniform and apodized SWGC, followed by numerical simulations for design verification. We experimentally demonstrate both types of SWGC. The apodized SWGC enables high coupling efficiency of -6.477 dB/facet with 3 dB bandwidth of 199 nm, whereas the uniform SWGC shows larger 3dB bandwidth of 263.5 nm but slightly lower coupling efficiency of -7.371 dB/facet.
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Zhou J, Lin PT. Midinfrared Multispectral Detection for Real-Time and Noninvasive Analysis of the Structure and Composition of Materials. ACS Sens 2018; 3:1322-1328. [PMID: 29972640 DOI: 10.1021/acssensors.8b00222] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
In situ material identification and object tracking have been demonstrated using a mid-infrared (mid-IR) robotic scanning system. This detection method is capable of inspecting materials noninvasively because the mid-IR spectrum overlaps with numerous characteristic absorption bands corresponding to various chemical function groups. The scanning system consisted of a fiber probe connected to a mid-IR tunable laser with a wavelength tuning range of λ = 2.45-3.75 μm. For the high-speed performance of the scanning system to be evaluated, a testing platform was constructed with an object plate rapidly rotating at ω = 231 rpm. The objects on the plate were SU-8 epoxy-based resin and polydimethylsiloxane, which were mid-IR absorptive while visibly transparent. Applying mid-IR multispectral scanning, the system was able to simultaneously track the object position and identify the composition by interpreting the spectral and spatial intensity variation. The mid-IR robotic scanning method thus provides a visualization system critical for process inspection in automatic manufacturing and high-throughput biomedical screening.
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15
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Wideband Ge-Rich SiGe Polarization-Insensitive Waveguides for Mid-Infrared Free-Space Communications. APPLIED SCIENCES-BASEL 2018. [DOI: 10.3390/app8071154] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
The recent development of quantum cascade lasers, with room-temperature emission in the mid-infrared range, opened new opportunities for the implementation of ultra-wideband communication systems. Specifically, the mid-infrared atmospheric transparency windows, comprising wavelengths between 3–5 µm and 8–14 µm, have great potential for free-space communications, as they provide a wide unregulated spectrum with low Mie and Rayleigh scattering and reduced background noise. Despite the great efforts devoted to the development of mid-infrared sources and detectors, little attention is dedicated to the management of polarization for signal processing. In this work, we used Ge-rich SiGe alloys to build a wideband and polarization-insensitive mid-infrared photonic platform. We showed that the gradual index change in the SiGe alloys enabled the design of waveguides with remarkably low birefringence, below 2 × 10−4, over ultra-wide wavelength ranges within both atmospheric transparency windows, near wavelengths of 3.5 µm and 9 µm. We also report on the design of a polarization-independent multimode interference device achieving efficient power splitting in an unprecedented 4.5-µm bandwidth at around 10-µm wavelength. The ultra-wideband polarization-insensitive building blocks presented here pave the way for the development of high-performance on-chip photonic circuits for next-generation mid-infrared free-space communication systems.
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Butcher HL, MacLachlan DG, Lee D, Thomson RR, Weidmann D. Demonstration and characterization of ultrafast laser-inscribed mid-infrared waveguides in chalcogenide glass IG2. OPTICS EXPRESS 2018; 26:10930-10943. [PMID: 29716022 DOI: 10.1364/oe.26.010930] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/01/2018] [Accepted: 04/06/2018] [Indexed: 06/08/2023]
Abstract
The first demonstration and characterization of ultrafast laser-inscribed mid-infrared (mid-IR) waveguides in Ge33As12Se55 chalcogenide glass (IG2) is presented. From mode profile and throughput measurements, combined with modelling, the characteristics of the waveguides inscribed in IG2 are studied at 7.8 μm, and compared to those of waveguides inscribed in gallium lanthanum sulfide for reference. Two methods to estimate the local variation of refractive index induced by the inscription process are presented, which indicate a variation of ~0.010 to 0.015 across the inscription parameters investigated. This variation, together with a higher robustness of the material to inscription and large transparency covering the entire mid-IR spectral domain, suggest that IG2 has great potential for integrated optical applications in the mid-IR developed through the ultrafast laser inscription method.
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17
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Jin T, Zhou J, Wang Z, Gutierrez-Osuna R, Ahn C, Hwang W, Park K, Lin PT. Real-Time Gas Mixture Analysis Using Mid-Infrared Membrane Microcavities. Anal Chem 2018; 90:4348-4353. [PMID: 29509404 DOI: 10.1021/acs.analchem.7b03599] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
Abstract
Real-time gas analysis on-a-chip was demonstrated using a mid-infrared (mid-IR) microcavity. Optical apertures for the microcavity were made of ultrathin silicate membranes embedded in a silicon chip using the complementary metal-oxide-semiconductor (CMOS) process. Fourier transform infrared spectroscopy (FTIR) shows that the silicate membrane is transparent in the range of 2.5-6.0 μm, a region that overlaps with multiple characteristic gas absorption lines and therefore enables gas detection applications. A test station integrating a mid-IR tunable laser, a microgas delivery system, and a mid-IR camera was assembled to evaluate the gas detection performance. CH4, CO2, and N2O were selected as analytes due to their strong absorption bands at λ = 3.25-3.50, 4.20-4.35, and 4.40-4.65 μm, which correspond to C-H, C-O, and O-N stretching, respectively. A short subsecond response time and high gas identification accuracy were achieved. Therefore, our chip-scale mid-IR sensor provides a new platform for an in situ, remote, and embedded gas monitoring system.
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Affiliation(s)
| | | | | | | | - Charles Ahn
- Crucialtec Co., LTD , Seongnam-si , Gyeonggi-do 13486 , South Korea
| | - Wonjun Hwang
- Crucialtec Co., LTD , Seongnam-si , Gyeonggi-do 13486 , South Korea
| | - Ken Park
- Crucialtec Co., LTD , Seongnam-si , Gyeonggi-do 13486 , South Korea
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Jin T, Lin HYG, Lin PT. Monolithically Integrated Si-on-AlN Mid-Infrared Photonic Chips for Real-Time and Label-Free Chemical Sensing. ACS APPLIED MATERIALS & INTERFACES 2017; 9:42905-42911. [PMID: 29171251 DOI: 10.1021/acsami.7b13307] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/07/2023]
Abstract
Chip-scale chemical sensors were demonstrated using optical waveguides consisting of amorphous silicon (a-Si) and aluminum nitride (AlN). A mid-infrared (mid-IR) transparent AlN thin film was prepared by room-temperature sputtering, which exhibited high Al/N elemental homogeneity. The Si-on-AlN waveguides were fabricated by a complementary metal-oxide-semiconductor process. A sharp fundamental mode and low optical loss of 2.21 dB/cm were obtained. Label-free chemical identification and real-time monitoring were performed by scanning the mode spectrum while the waveguide was exposed to various chemicals. Continuous tracing of heptane and methanol was accomplished by measuring the waveguide intensity attenuation at λ = 2.5-3.0 μm, which included the characteristic -CH and -OH absorptions. The monolithically integrated Si-on-AlN waveguides established a new sensor platform that can operate over a broad mid-IR regime, thus enabling photonic chips for label-free chemical detection.
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Affiliation(s)
| | - Hao-Yu Greg Lin
- Center for Nanoscale Systems, Harvard University , 11 Oxford Street, Cambridge, Massachusetts 02138, United States
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19
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Jin T, Li L, Zhang B, Lin HYG, Wang H, Lin PT. Monolithic Mid-Infrared Integrated Photonics Using Silicon-on-Epitaxial Barium Titanate Thin Films. ACS APPLIED MATERIALS & INTERFACES 2017; 9:21848-21855. [PMID: 28580780 DOI: 10.1021/acsami.7b02681] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/07/2023]
Abstract
Broadband mid-infrared (mid-IR) photonic circuits that integrate silicon waveguides and epitaxial barium titanate (BTO) thin films are demonstrated using the complementary metal-oxide-semiconductor process. The epitaxial BTO thin films are grown on lanthanum aluminate (LAO) substrates by the pulsed laser deposition technique, wherein a broad infrared transmittance between λ = 2.5 and 7 μm is observed. The optical waveguiding direction is defined by the high-refractive-index amorphous Si (a-Si) ridge structure developed on the BTO layer. Our waveguides show a sharp fundamental mode over the broad mid-IR spectrum, whereas its optical field distribution between the a-Si and BTO layers can be modified by varying the height of the a-Si ridge. With the advantages of broad mid-IR transparency and the intrinsic electro-optic properties, our monolithic Si on a ferroelectric BTO platform will enable tunable mid-IR microphotonics that are desired for high-speed optical logic gates and chip-scale biochemical sensors.
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Affiliation(s)
| | | | | | - Hao-Yu Greg Lin
- Center for Nanoscale Systems, Harvard University , 11 Oxford Street, Cambridge, Massachusetts 02138, United States
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20
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Ramirez JM, Vakarin V, Gilles C, Frigerio J, Ballabio A, Chaisakul P, Roux XL, Alonso-Ramos C, Maisons G, Vivien L, Carras M, Isella G, Marris-Morini D. Low-loss Ge-rich Si 0.2Ge 0.8 waveguides for mid-infrared photonics. OPTICS LETTERS 2017; 42:105-108. [PMID: 28059186 DOI: 10.1364/ol.42.000105] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/06/2023]
Abstract
We demonstrate low-loss Ge-rich Si0.2Ge0.8 waveguides on Si1-xGex (x from 0 to 0.79) graded substrates operating in the mid-infrared wavelength range at λ=4.6 μm. Propagation losses as low as (1.5±0.5)dB/cm and (2±0.5)dB/cm were measured for the quasi-TE and quasi-TM polarizations, respectively. A total coupling loss (input/output) of only 10 dB was found for waveguide widths larger than 7 μm due to a good fiber-waveguide mode matching. Near-field optical mode profiles measured at the output waveguide facet allowed us to inspect the optical mode and precisely measure the modal effective area of each waveguide providing a good correlation between experiments and simulations. These results put forward the potential of low-index-contrast Si1-xGex waveguides with high Ge concentration as fundamental blocks for mid-infrared photonic integrated circuits.
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21
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Singh N, Casas-Bedoya A, Hudson DD, Read A, Mägi E, Eggleton BJ. Mid-IR absorption sensing of heavy water using a silicon-on-sapphire waveguide. OPTICS LETTERS 2016; 41:5776-5779. [PMID: 27973499 DOI: 10.1364/ol.41.005776] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/06/2023]
Abstract
We demonstrate a compact silicon-on-sapphire (SOS) strip waveguide sensor for mid-IR absorption spectroscopy. This device can be used for gas and liquid sensing, especially to detect chemically similar molecules and precisely characterize extremely absorptive liquids that are difficult to detect by conventional infrared transmission techniques. We reliably measure concentrations up to 0.25% of heavy water (D2O) in a D2O-H2O mixture at its maximum absorption band at around 4 μm. This complementary metal-oxide-semiconductor (CMOS) compatible SOS D2O sensor is promising for applications such as measuring body fat content or detection of coolant leakage in nuclear reactors.
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Haas J, Mizaikoff B. Advances in Mid-Infrared Spectroscopy for Chemical Analysis. ANNUAL REVIEW OF ANALYTICAL CHEMISTRY (PALO ALTO, CALIF.) 2016; 9:45-68. [PMID: 27070183 DOI: 10.1146/annurev-anchem-071015-041507] [Citation(s) in RCA: 118] [Impact Index Per Article: 14.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/15/2023]
Abstract
Infrared spectroscopy in the 3-20 μm spectral window has evolved from a routine laboratory technique into a state-of-the-art spectroscopy and sensing tool by benefitting from recent progress in increasingly sophisticated spectra acquisition techniques and advanced materials for generating, guiding, and detecting mid-infrared (MIR) radiation. Today, MIR spectroscopy provides molecular information with trace to ultratrace sensitivity, fast data acquisition rates, and high spectral resolution catering to demanding applications in bioanalytics, for example, and to improved routine analysis. In addition to advances in miniaturized device technology without sacrificing analytical performance, selected innovative applications for MIR spectroscopy ranging from process analysis to biotechnology and medical diagnostics are highlighted in this review.
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Affiliation(s)
- Julian Haas
- Institute of Analytical and Bioanalytical Chemistry, Ulm University, 89069 Ulm, Germany;
| | - Boris Mizaikoff
- Institute of Analytical and Bioanalytical Chemistry, Ulm University, 89069 Ulm, Germany;
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23
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Affiliation(s)
- Markus Sieger
- Institute
of Analytical and
Bioanalytical Chemistry, Ulm University, Albert-Einstein-Allee 11, 89081 Ulm, Germany
| | - Boris Mizaikoff
- Institute
of Analytical and
Bioanalytical Chemistry, Ulm University, Albert-Einstein-Allee 11, 89081 Ulm, Germany
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24
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Yue W, Wang Z, Whittaker J, Schedin F, Wu Z, Han J. Resonance control of mid-infrared metamaterials using arrays of split-ring resonator pairs. NANOTECHNOLOGY 2016; 27:055303. [PMID: 26751676 DOI: 10.1088/0957-4484/27/5/055303] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/05/2023]
Abstract
We present our design, fabrication and characterization of resonance-controllable metamaterials operating at mid-infrared wavelengths. The metamaterials are composed of pairs of back-to-back or face-to-face U-shape split-ring resonators (SRRs). Transmission spectra of the metamaterials are measured using Fourier-transform infrared spectroscopy. The results show that the transmission resonance is dependent on the distance between the two SRRs in each SRR pair. The dips in the transmission spectrum shift to shorter wavelengths with increasing distance between the two SRRs for both the back-to-back and face-to-face SRR pairs. The position of the resonance dips in the spectrum can hence be controlled by the relative position of the SRRs. This mechanism of resonance control offers a promising way of developing metamaterials with tunability for optical filters and bio/chemical sensing devices in integrated nano-optics.
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Affiliation(s)
- Weisheng Yue
- National Graphene Institute, University of Manchester, Oxford Road, Manchester M13 9PL, UK
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25
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Singh N, Hudson DD, Eggleton BJ. Silicon-on-sapphire pillar waveguides for Mid-IR supercontinuum generation. OPTICS EXPRESS 2015; 23:17345-17354. [PMID: 26191744 DOI: 10.1364/oe.23.017345] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/04/2023]
Abstract
We propose pillar integrated silicon waveguides to exploit the entire transparent window of silicon. These geometries posses a broad and flat dispersion (from 2 to 6 μm) with four zero dispersion wavelengths. We calculate supercontinuum generation spanning over two octaves (2 to >8 μm) with long wavelengths interacting weakly with the lossy substrate. These structures have higher mode confinement in the silicon - away from the substrate, which makes them substrate independent and are promising for exploring new nonlinear phenomena and highly sensitive molecular sensing over the entire silicon's transparency range.
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26
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Lin PT, Giammarco J, Borodinov N, Savchak M, Singh V, Kimerling LC, Tan DTH, Richardson KA, Luzinov I, Agarwal A. Label-free water sensors using hybrid polymer-dielectric mid-infrared optical waveguides. ACS APPLIED MATERIALS & INTERFACES 2015; 7:11189-11194. [PMID: 25924561 DOI: 10.1021/acsami.5b01013] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/04/2023]
Abstract
A chip-scale mid-IR water sensor was developed using silicon nitride (SiN) waveguides coated with poly(glycidyl methacrylate) (PGMA). The label-free detection was conducted at λ=2.6-2.7 μm because this spectral region overlaps with the characteristic O-H stretch absorption while being transparent to PGMA and SiN. Through the design of a hybrid waveguide structure, we were able to tailor the mid-IR evanescent wave into the PGMA layer and the surrounding water and, consequently, to enhance the light-analyte interaction. A 7.6 times enhancement of sensitivity is experimentally demonstrated and explained by material integration engineering as well as waveguide mode analysis. Our sensor platform made by polymer-dielectric hybrids can be applied to other regions of the mid-IR spectrum to probe other analytes and can ultimately achieve a multispectral sensor on-a-chip.
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Affiliation(s)
- Pao Tai Lin
- †Materials Processing Center, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, United States
- §Photonics Devices and Systems Group, Singapore University of Technology and Design, Singapore 487372, Singapore
| | - James Giammarco
- ‡Department of Materials Science and Engineering, Clemson University, Clemson, South Carolina 29634, United States
| | - Nikolay Borodinov
- ‡Department of Materials Science and Engineering, Clemson University, Clemson, South Carolina 29634, United States
| | - Mykhailo Savchak
- ‡Department of Materials Science and Engineering, Clemson University, Clemson, South Carolina 29634, United States
| | - Vivek Singh
- †Materials Processing Center, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, United States
| | - Lionel C Kimerling
- †Materials Processing Center, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, United States
| | - Dawn T H Tan
- §Photonics Devices and Systems Group, Singapore University of Technology and Design, Singapore 487372, Singapore
| | | | - Igor Luzinov
- ‡Department of Materials Science and Engineering, Clemson University, Clemson, South Carolina 29634, United States
| | - Anu Agarwal
- †Materials Processing Center, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, United States
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27
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Chen Y, Lin H, Hu J, Li M. Heterogeneously integrated silicon photonics for the mid-infrared and spectroscopic sensing. ACS NANO 2014; 8:6955-61. [PMID: 24884013 DOI: 10.1021/nn501765k] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/19/2023]
Abstract
Besides being the foundational material for microelectronics, crystalline silicon has long been used for the production of infrared lenses and mirrors. More recently, silicon has become the key material to achieve large-scale integration of photonic devices for on-chip optical interconnect and signal processing. For optics, silicon has significant advantages: it offers a very high refractive index and is highly transparent in the spectral range from 1.2 to 8 μm. To fully exploit silicon’s superior performance in a remarkably broad range and to enable new optoelectronic functionalities, here we describe a general method to integrate silicon photonic devices on arbitrary foreign substrates. In particular, we apply the technique to integrate silicon microring resonators on mid-infrared compatible substrates for operation in the mid-infrared. These high-performance mid-infrared optical resonators are utilized to demonstrate, for the first time, on-chip cavity-enhanced mid-infrared spectroscopic analysis of organic chemicals with a limit of detection of less than 0.1 ng.
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28
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Ryckeboer E, Bockstaele R, Vanslembrouck M, Baets R. Glucose sensing by waveguide-based absorption spectroscopy on a silicon chip. BIOMEDICAL OPTICS EXPRESS 2014; 5:1636-48. [PMID: 24877021 PMCID: PMC4026885 DOI: 10.1364/boe.5.001636] [Citation(s) in RCA: 40] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/13/2013] [Revised: 03/21/2014] [Accepted: 04/06/2014] [Indexed: 05/21/2023]
Abstract
In this work, we demonstrate in vitro detection of glucose by means of a lab-on-chip absorption spectroscopy approach. This optical method allows label-free and specific detection of glucose. We show glucose detection in aqueous glucose solutions in the clinically relevant concentration range with a silicon-based optofluidic chip. The sample interface is a spiral-shaped rib waveguide integrated on a silicon-on-insulator (SOI) photonic chip. This SOI chip is combined with micro-fluidics in poly(dimethylsiloxane) (PDMS). We apply aqueous glucose solutions with different concentrations and monitor continuously how the transmission spectrum changes due to glucose. Based on these measurements, we derived a linear regression model, to relate the measured glucose spectra with concentration with an error-of-fitting of only 1.14 mM. This paper explains the challenges involved and discusses the optimal configuration for on-chip evanescent absorption spectroscopy. In addition, the prospects for using this sensor for glucose detection in complex physiological media (e.g. serum) is briefly discussed.
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Affiliation(s)
- E. Ryckeboer
- Photonics Research Group, INTEC Department, Ghent University - IMEC, Sint-Pietersnieuwstraat 41,9000 Ghent,
Belgium
- Center for Nano- and Biophotonics (NB-Photonics), Ghent University,
Belgium
| | - R. Bockstaele
- Photonics Research Group, INTEC Department, Ghent University - IMEC, Sint-Pietersnieuwstraat 41,9000 Ghent,
Belgium
- Center for Nano- and Biophotonics (NB-Photonics), Ghent University,
Belgium
| | - M. Vanslembrouck
- Photonics Research Group, INTEC Department, Ghent University - IMEC, Sint-Pietersnieuwstraat 41,9000 Ghent,
Belgium
- Center for Nano- and Biophotonics (NB-Photonics), Ghent University,
Belgium
| | - R. Baets
- Photonics Research Group, INTEC Department, Ghent University - IMEC, Sint-Pietersnieuwstraat 41,9000 Ghent,
Belgium
- Center for Nano- and Biophotonics (NB-Photonics), Ghent University,
Belgium
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29
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Singh V, Lin PT, Patel N, Lin H, Li L, Zou Y, Deng F, Ni C, Hu J, Giammarco J, Soliani AP, Zdyrko B, Luzinov I, Novak S, Novak J, Wachtel P, Danto S, Musgraves JD, Richardson K, Kimerling LC, Agarwal AM. Mid-infrared materials and devices on a Si platform for optical sensing. SCIENCE AND TECHNOLOGY OF ADVANCED MATERIALS 2014; 15:014603. [PMID: 27877641 PMCID: PMC5090602 DOI: 10.1088/1468-6996/15/1/014603] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/31/2013] [Revised: 01/30/2014] [Accepted: 12/01/2013] [Indexed: 05/14/2023]
Abstract
In this article, we review our recent work on mid-infrared (mid-IR) photonic materials and devices fabricated on silicon for on-chip sensing applications. Pedestal waveguides based on silicon are demonstrated as broadband mid-IR sensors. Our low-loss mid-IR directional couplers demonstrated in SiN x waveguides are useful in differential sensing applications. Photonic crystal cavities and microdisk resonators based on chalcogenide glasses for high sensitivity are also demonstrated as effective mid-IR sensors. Polymer-based functionalization layers, to enhance the sensitivity and selectivity of our sensor devices, are also presented. We discuss the design of mid-IR chalcogenide waveguides integrated with polycrystalline PbTe detectors on a monolithic silicon platform for optical sensing, wherein the use of a low-index spacer layer enables the evanescent coupling of mid-IR light from the waveguides to the detector. Finally, we show the successful fabrication processing of our first prototype mid-IR waveguide-integrated detectors.
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Affiliation(s)
- Vivek Singh
- Microphotonics Center, Massachusetts Institute of Technology, Cambridge, MA 02139, USA
| | - Pao Tai Lin
- Microphotonics Center, Massachusetts Institute of Technology, Cambridge, MA 02139, USA
| | - Neil Patel
- Microphotonics Center, Massachusetts Institute of Technology, Cambridge, MA 02139, USA
| | - Hongtao Lin
- Department of Materials Science and Engineering, University of Delaware, Newark, DE 19716, USA
| | - Lan Li
- Department of Materials Science and Engineering, University of Delaware, Newark, DE 19716, USA
| | - Yi Zou
- Department of Materials Science and Engineering, University of Delaware, Newark, DE 19716, USA
| | - Fei Deng
- Department of Materials Science and Engineering, University of Delaware, Newark, DE 19716, USA
| | - Chaoying Ni
- Department of Materials Science and Engineering, University of Delaware, Newark, DE 19716, USA
| | - Juejun Hu
- Department of Materials Science and Engineering, University of Delaware, Newark, DE 19716, USA
| | - James Giammarco
- Department of Materials Science and Engineering, Clemson University, Clemson, SC 29634, USA
| | - Anna Paola Soliani
- Department of Materials Science and Engineering, Clemson University, Clemson, SC 29634, USA
| | - Bogdan Zdyrko
- Department of Materials Science and Engineering, Clemson University, Clemson, SC 29634, USA
| | - Igor Luzinov
- Department of Materials Science and Engineering, Clemson University, Clemson, SC 29634, USA
| | - Spencer Novak
- Department of Materials Science and Engineering, Clemson University, Clemson, SC 29634, USA
| | - Jackie Novak
- Department of Materials Science and Engineering, Clemson University, Clemson, SC 29634, USA
| | - Peter Wachtel
- Department of Materials Science and Engineering, Clemson University, Clemson, SC 29634, USA
| | - Sylvain Danto
- Department of Materials Science and Engineering, Clemson University, Clemson, SC 29634, USA
| | - J David Musgraves
- Department of Materials Science and Engineering, Clemson University, Clemson, SC 29634, USA
| | - Kathleen Richardson
- Department of Materials Science and Engineering, Clemson University, Clemson, SC 29634, USA
- College of Optics and Photonics, CREOL, University of Central Florida, Orlando, FL 32816, USA
| | - Lionel C Kimerling
- Microphotonics Center, Massachusetts Institute of Technology, Cambridge, MA 02139, USA
| | - Anuradha M Agarwal
- Microphotonics Center, Massachusetts Institute of Technology, Cambridge, MA 02139, USA
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30
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Lin PT, Kwok SW, Lin HYG, Singh V, Kimerling LC, Whitesides GM, Agarwal A. Mid-infrared spectrometer using opto-nanofluidic slot-waveguide for label-free on-chip chemical sensing. NANO LETTERS 2014; 14:231-238. [PMID: 24328355 DOI: 10.1021/nl403817z] [Citation(s) in RCA: 38] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/03/2023]
Abstract
A mid-infrared (mid-IR) spectrometer for label-free on-chip chemical sensing was developed using an engineered nanofluidic channel consisting of a Si-liquid-Si slot-structure. Utilizing the large refractive index contrast (Δn ∼ 2) between the liquid core of the waveguide and the Si cladding, a broadband mid-IR lightwave can be efficiently guided and confined within a nanofluidic capillary (≤100 nm wide). The optical-field enhancement, together with the direct interaction between the probe light and the analyte, increased the sensitivity for chemical detection by 50 times when compared to evanescent-wave sensing. This spectrometer distinguished several common organic liquids (e.g., n-bromohexane, toluene, isopropanol) accurately and could determine the ratio of chemical species (e.g., acetonitrile and ethanol) at low concentration (<5 μL/mL) in a mixture through spectral scanning over their characteristic absorption peaks in the mid-IR regime. The combination of CMOS-compatible planar mid-IR microphotonics, and a high-throughput nanofluidic sensor system, provides a unique platform for chemical detection.
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Affiliation(s)
- Pao Tai Lin
- Microphotonics Center, Massachusetts Institute of Technology , 77 Massachusetts Avenue, Cambridge, Massachusetts 02139, United States
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