Silicon-organic hybrid electro-optical devices

Organic materials combined with strongly guiding silicon waveguides open the route to highly efficient electro-optical devices. Modulators based on the so-called silicon-organic hybrid (SOH) platform have only recently shown frequency responses up to 100 GHz, high-speed operation beyond 112 Gbit/s with fJ/bit power consumption. In this paper, we review the SOH platform and discuss important devices such as Mach-Zehnder and IQ-modulators based on the linear electro-optic effect. We further show liquid-crystal phase-shifters with a voltage-length product as low as V pi L = 0.06 V.mm and sub-mu W power consumption as required for slow optical switching or tuning optical filters and devices

Quantum Modelling of Electro-Optic Modulators

Many components that are employed in quantum information and communication systems are well known photonic devices encountered in standard optical fiber communication systems, such as optical beamsplitters, waveguide couplers and junctions, electro-optic modulators and optical fiber links. The use of these photonic devices is becoming increasingly important especially in the context of their possible integration either in a specifically designed system or in an already deployed end-to-end fiber link. Whereas the behavior of these devices is well known under the classical regime, in some cases their operation under quantum conditions is less well understood. This paper reviews the salient features of the quantum scattering theory describing both the operation of the electro-optic phase and amplitude modulators in discrete and continuous-mode formalisms. This subject is timely and of importance in light of the increasing utilization of these devices in a variety of systems, including quantum key distribution and single-photon wavepacket measurement and conformation. In addition, the paper includes a tutorial development of the use of these models in selected but yet important applications, such as single and multi-tone modulation of photons, two-photon interference with phase-modulated light or the description of amplitude modulation as a quantum operation.Comment: 29 pages, 10 figures, Laser and Photonics Reviews (in press

Programmable photonic circuits

[EN] The growing maturity of integrated photonic technology makes it possible to build increasingly large and complex photonic circuits on the surface of a chip. Today, most of these circuits are designed for a specific application, but the increase in complexity has introduced a generation of photonic circuits that can be programmed using software for a wide variety of functions through a mesh of on-chip waveguides, tunable beam couplers and optical phase shifters. Here we discuss the state of this emerging technology, including recent developments in photonic building blocks and circuit architectures, as well as electronic control and programming strategies. We cover possible applications in linear matrix operations, quantum information processing and microwave photonics, and examine how these generic chips can accelerate the development of future photonic circuits by providing a higher-level platform for prototyping novel optical functionalities without the need for custom chip fabricationBogaerts, W.; Pérez-López, D.; Capmany Francoy, J.; Miller, DAB.; Poon, J.; Englund, D.; Morichetti, F.... (2020). Programmable photonic circuits. Nature. 586(7828):207-216. https://doi.org/10.1038/s41586-020-2764-0S2072165867828Chen, X. et al. The emergence of silicon photonics as a flexible technology platform. Proc. IEEE 106, 2101–2116 (2018).Smit, M., Williams, K. & van der Tol, J. Past, present, and future of InP-based photonic integration. APL Photonics 4, 050901 (2019).Capmany, J. & Perez, D. Programmable Integrated Photonics (Oxford Univ. Press, 2020). The first book on the subject of programmable photonics gives a detailed overview of the fundamental principles, architectures and potential applications.Marpaung, D., Yao, J. & Capmany, J. Integrated microwave photonics. Nat. Photon. 13, 80–90 (2019).Zhuang, L., Roeloffzen, C. G. H., Hoekman, M., Boller, K. & Lowery, A. J. Programmable photonic signal processor chip for radiofrequency applications. Optica 2, 854–859 (2015).Shen, Y. et al. Deep learning with coherent nanophotonic circuits. Nat. Photon. 11, 441–446 (2017).Harris, N. C. et al. Linear programmable nanophotonic processors. Optica 5, 1623–1631 (2018). One of the largest-scale demonstrations of a programmable photonic circuit, using a silicon photonics forward-only mesh that maps 26 input modes onto 26 output modes, for use in deep learning and quantum information processing.Miller, D. A. B. Self-configuring universal linear optical component. Photon. Res. 1, 1–15 (2013). This foundational paper in the field of programmable photonics is the first to bring together waveguide meshes with self-configuration algorithms that require no active computation, including the concept of the self-aligning beam coupler.Carolan, J. et al. Universal linear optics. Science 349, 711–716 (2015).Harris, N. C. et al. Large-scale quantum photonic circuits in silicon. Nanophotonics 5, 456–468 (2016).Notaros, J. et al. Programmable dispersion on a photonic integrated circuit for classical and quantum applications. Opt. Express 25, 21275–21285 (2017).Clements, W. R., Humphreys, P. C., Metcalf, B. J., Kolthammer, W. S. & Walmsley, I. A. An optimal design for universal multiport interferometers. Optica 12, 1460–1465 (2016).Perez-Lopez, D. Programmable integrated silicon photonics waveguide meshes: optimized designs and control algorithms. IEEE J. Sel. Top. Quantum Electron. 26, 8301312 (2020).Ribeiro, A., Ruocco, A., Vanacker, L. & Bogaerts, W. Demonstration of a 4×4-port universal linear circuit. Optica 3, 1348–1357 (2016).Harris, N. C. et al. Quantum transport simulations in a programmable nanophotonic processor. Nat. Photon. 11, 447–452 (2017).Mennea, P. L. et al. Modular linear optical circuits. Optica 5, 1087–1090 (2018).Taballione, C. et al. 8×8 programmable quantum photonic processor based on silicon nitride waveguides. In Frontiers in Optics, JTu3A.58 (Optical Society of America, 2018). A demonstration of an 8 × 8 forward-only programmable linear circuit in silicon nitride that benefits from the notably low optical losses of this material and is therefore attractive for linear quantum operations on single photons.Perez, D. et al. Silicon photonics rectangular universal interferometer. Laser Photonics Rev. 11, 1700219 (2017).Xie, Y. et al. Programmable optical processor chips: toward photonic RF filters with DSP-level flexibility and MHz-band selectivity. Nanophotonics 7, 421–454 (2017). A comprehensive overview of the various ways in which a programmable photonic circuit can be used to process microwave signals, and on how this type of circuit is transitioning from custom ASPICs to generic programmable PICs.Hall, T. J. & Hasan, M. Universal discrete Fourier optics RF photonic integrated circuit architecture. Opt. Express 24, 7600–7610 (2016).Dyakonov, I. V. et al. Reconfigurable photonics on a glass chip. Phys. Rev. Appl. 10, 044048 (2018).Shokraneh, F., Geoffroy-Gagnon, S., Nezami, M. S. & Liboiron-Ladouceur, O. A single layer neural network implemented by a 4×4 MZI-based optical processor. IEEE Photonics J. 11, 4501612 (2019).Lu, L., Zhou, L. & Chen, J. Programmable SCOW mesh silicon photonic processor for linear unitary operator. Micromachines 10, 646 (2019).Qiang, X. et al. Large-scale silicon quantum photonics implementing arbitrary two-qubit processing. Nat. Photon. 12, 534–539 (2018).Wang, J. et al. Multidimensional quantum entanglement with large-scale integrated optics. Science 360, 285–291 (2018).Schaeff, C., Polster, R., Huber, M., Ramelow, S. & Zeilinger, A. Experimental access to higher-dimensional entangled quantum systems using integrated optics. Optica 2, 523–529 (2015).Shadbolt, P. J. et al. Generating, manipulating and measuring entanglement and mixture with a reconfigurable photonic circuit. Nat. Photon. 6, 45–49 (2012).Miller, D. A. B. Waves, modes, communications, and optics: a tutorial. Adv. Opt. Photonics 11, 679 (2019).Miller, D. A. B. Self-aligning universal beam coupler. Opt. Express 21, 6360–6370 (2013).Miller, D. A. B. Perfect optics with imperfect components. Optica 2, 747–750 (2015).Annoni, A. et al. Unscrambling light—automatically undoing strong mixing between modes. Light Sci. Appl. 6, e17110 (2017). Early demonstration of a forward-only programmable mesh used to unmix different modes in a waveguide, implementing integrated transparent detectors that measure the light intensity in the waveguide without inducing additional optical loss.Pai, S. et al. Parallel programming of an arbitrary feedforward photonic network. IEEE J. Sel. Top. Quantum Electron. 25, 6100813 (2020).Reck, M., Zeilinger, A., Bernstein, H. J. & Bertani, P. Experimental realization of any discrete unitary operator. Phys. Rev. Lett. 73, 58–61 (1994).Wang, M., Alves, A. R., Xing, Y. & Bogaerts, W. Tolerant, broadband tunable 2×2 coupler circuit. Opt. Express 28, 5555–5566 (2020).Pérez-López, D., Gutierrez, A. M., Sánchez, E., DasMahapatra, P. & Capmany, J. Integrated photonic tunable basic units using dual-drive directional couplers. Opt. Express 27, 38071 (2019).Choutagunta, K., Roberts, I., Miller, D. A. B. & Kahn, J. M. Adapting Mach–Zehnder mesh equalizers in direct-detection mode-division-multiplexed links. J. Light. Technol. 38, 723–735 (2020).Miller, D. A. B. Analyzing and generating multimode optical fields using self-configuring networks. Optica 7, 794–801 (2020).Morizur, J.-F. et al. Programmable unitary spatial mode manipulation. J. Opt. Soc. Am. A 27, 2524 (2010).Labroille, G. et al. Efficient and mode selective spatial mode multiplexer based on multi-plane light conversion. Opt. Express 22, 15599–15607 (2014).Tanomura, R., Tang, R., Ghosh, S., Tanemura, T. & Nakano, T. Robust integrated optical unitary converter using multiport directional couplers. J. Light. Technol. 38, 60–66 (2020).Miller, D. A. B. Setting up meshes of interferometers – reversed local light interference method. Opt. Express 25, 29233 (2017).Li, H. W. et al. Calibration and high fidelity measurement of a quantum photonic chip. New J. Phys. 15, 063017 (2013).Cong, G. et al. Arbitrary reconfiguration of universal silicon photonic circuits by bacteria foraging algorithm to achieve reconfigurable photonic digital-to-analog conversion. Opt. Express 27, 24914 (2019).Pérez, D. et al. Multipurpose silicon photonics signal processor core. Nat. Commun. 8, 1–9 (2017). The first experimental demonstration of a recirculating waveguide mesh with seven unit cells that can be programmed to perform more than a hundred different functions.Pérez, D., Gasulla, I. & Capmany, J. Field-programmable photonic arrays. Opt. Express 26, 27265 (2018).Rahim, A., Spuesens, T., Baets, R. & Bogaerts, W. Open-access silicon photonics: current status and emerging initiatives. Proc. IEEE 106, 2313–2330 (2018).Munoz, P. et al. Foundry developments toward silicon nitride photonics from visible to the mid-infrared. IEEE J. Sel. Top. Quantum Electron. 25, 8200513 (2019).Teng, M. et al. Miniaturized silicon photonics devices for integrated optical signal processors. J. Light. Technol. 38, 6–17 (2020).Sacher, W. D. et al. Monolithically integrated multilayer silicon nitride-on-silicon waveguide platforms for 3-D photonic circuits and devices. Proc. IEEE 106, 2232–2245 (2018).Baudot, C. et al. Developments in 300mm silicon photonics using traditional CMOS fabrication methods and materials. In 2017 IEEE Int. Electron Devices Meeting, 765–768 (IEEE, 2017).Fahrenkopf, N. M. et al. The AIM photonics MPW: a highly accessible cutting edge technology for rapid prototyping of photonic integrated circuits. IEEE J. Sel. Top. Quantum Electron. 25, 8201406 (2019).Chiles, J. et al. Multi-planar amorphous silicon photonics with compact interplanar couplers, cross talk mitigation, and low crossing loss. APL Photonics 2, 116101 (2017).Van Campenhout, J., Green, W. M. J., Assefa, S. & Vlasov, Y. A. Integrated NiSi waveguide heaters for CMOS-compatible silicon thermo-optic devices. Opt. Lett. 35, 1013–1015 (2010).Masood, A. et al. Comparison of heater architectures for thermal control of silicon photonic circuits. In Proc. 10th Int. Conference on Group IV Photonics 83–84 (IEEE, 2013).Milanizadeh, M., Aguiar, D., Melloni, A. & Morichetti, F. Canceling thermal cross-talk effects in photonic integrated circuits. J. Light. Technol. 37, 1325–1332 (2019).Soref, R. A. & Bennett, B. R. Electrooptical effects in silicon. IEEE J. Quantum Electron. 23, 123–129 (1987).Reed, G. T., Mashanovich, G., Gardes, F. Y. & Thomson, D. J. Silicon optical modulators. Nat. Photon. 4, 518–526 (2010); corrigendum 4, 660 (2010).Memon, F. A. et al. Silicon oxycarbide platform for integrated photonics. J. Light. Technol. 38, 784–791 (2020).Jin, W., Polcawich, R. G., Morton, P. A. & Bowers, J. E. Piezoelectrically tuned silicon nitride ring resonator. Opt. Express 26, 3174–3187 (2018).Hosseini, N. et al. Stress-optic modulator in TriPleX platform using a piezoelectric lead zirconate titanate (PZT) thin film. Opt. Express 23, 14018 (2015).De Cort, W., Beeckman, J., Claes, T., Neyts, K. & Baets, R. Wide tuning of silicon-on-insulator ring resonators with a liquid crystal cladding. Opt. Lett. 36, 3876–3878 (2011).Xing, Y. et al. Digitally controlled phase shifter using an SOI slot waveguide with liquid crystal infiltration. IEEE Photonics Technol. Lett. 27, 1269–1272 (2015).Abel, S. et al. Large Pockels effect in micro- and nanostructured barium titanate integrated on silicon. Nat. Mater. 18, 42–47 (2019).Desiatov, B., Shams-Ansari, A., Zhang, M., Wang, C. & Lončar, M. Ultra-low-loss integrated visible photonics using thin-film lithium niobate. Optica 6, 380 (2019).Alexander, K. et al. Nanophotonic Pockels modulators on a silicon nitride platform. Nat. Commun. 9, 3444 (2018).Leuthold, J. et al. Silicon-organic hybrid electro-optical devices. IEEE J. Sel. Top. Quantum Electron. 19, 114–126 (2013).Errando-Herranz, C. et al. MEMS for photonic integrated circuits. IEEE J. Sel. Top. Quantum Electron. 26, 8200916 (2020).Quack, N. et al. MEMS-enabled silicon photonic integrated devices and circuits. IEEE J. Quantum Electron. 56, 8400210 (2020).Hoessbacher, C. et al. The plasmonic memristor: a latching optical switch. Optica 1, 198 (2014).Ríos, C. et al. Integrated all-photonic non-volatile multi-level memory. Nat. Photon. 9, 725–732 (2015).Wuttig, M., Bhaskaran, H. & Taubner, T. Phase-change materials for non-volatile photonic applications. Nat. Photon. 11, 465–476 (2017).Morichetti, F. et al. Non-invasive on-chip light observation by contactless waveguide conductivity monitoring. IEEE J. Sel. Top. Quantum Electron. 20, 292–301 (2014).Jayatilleka, H., Shoman, H., Chrostowski, L. & Shekhar, S. Photoconductive heaters enable control of large-scale silicon photonic ring resonator circuits. Optica 6, 84–91 (2019).Grillanda, S. et al. Non-invasive monitoring and control in silicon photonics using CMOS integrated electronics. Optica 1, 129 (2014).Annoni, A. et al. Automated routing and control of silicon photonic switch fabrics. IEEE J. Sel. Top. Quantum Electron. 22, 169–176 (2016).Dumais, P. et al. Silicon photonic switch subsystem with 900 monolithically integrated calibration photodiodes and 64-fiber package. J. Light. Technol. 36, 233–238 (2018).Chen, H., Luo, X. & Poon, A. W. Cavity-enhanced photocurrent generation by 1.55 μm wavelengths linear absorption in a p–i–n diode embedded silicon microring resonator. Appl. Phys. Lett. 95, 171111 (2009).Ribeiro, A. & Bogaerts, W. Digitally controlled multiplexed silicon photonics phase shifter using heaters with integrated diodes. Opt. Express 25, 29778 (2017).Zimmermann, L. et al. BiCMOS silicon photonics platform. In Optical Fiber Communication Conference Th4E-5 (Optical Society of America, 2015).Orcutt, J. S. et al. Nanophotonic integration in state-of-the-art CMOS foundries. Opt. Express 19, 2335–2346 (2011).Stojanović, V. et al. Monolithic silicon-photonic platforms in state-of-the-art CMOS SOI processes. Opt. Express 26, 13106 (2018).Carroll, L. et al. Photonic packaging: transforming silicon photonic integrated circuits into photonic devices. Appl. Sci. 6, 426 (2016).Patterson, D., De Sousa, I. & Archard, L.-M. The future of packaging with silicon photonics. Chip Scale Rev. 21, 1–10 (2017).Ribeiro, A., Declercq, S., Khan, U., Wang, M. & Van Iseghem, L. Column-row addressing of thermo-optic phase shifters for controlling large silicon photonic circuits. IEEE J. Sel. Top. Quantum Electron. 26, 6100708 (2020).Pantouvaki, M. et al. Active components for 50 Gb/s NRZ-OOK optical interconnects in a silicon photonics platform. J. Light. Technol. 35, 631–638 (2017).Chen, H. et al. 100-Gbps RZ data reception in 67-GHz Si-contacted germanium waveguide p-i-n photodetectors. J. Light. Technol. 35, 722–726 (2017).Pérez, D., Gasulla, I. & Capmany, J. Toward programmable microwave photonics processors. J. Light. 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All-optical hash code generation and verification for low latency communications. Opt. Express 21, 23873 (2013).Wang, J., Sciarrino, F., Laing, A. & Thompson, M. G. Integrated photonic quantum technologies. Nat. Photon. 14, 273–284 (2019).Norberg, E. J., Guzzon, R. S., Parker, J. S., Johansson, L. A. & Coldren, L. A. Programmable photonic microwave filters monolithically integrated in InP-InGaAsP. J. Light. Technol. 29, 1611–1619 (2011).Wang, J. et al. Reconfigurable radio-frequency arbitrary waveforms synthesized in a silicon photonic chip. Nat. Commun. 6, 5957 (2015).Burla, M. et al. On-chip CMOS compatible reconfigurable optical delay line with separate carrier tuning for microwave photonic signal processing. Opt. Express 19, 21475 (2011).Liu, L. et al. Photonic measurement of microwave frequency using a silicon microdisk resonator. Opt. Commun. 335, 266–270 (2015).Perez-Lopez, D., Sanchez, E. & Capmany, J. Programmable true-time delay lines using integrated waveguide meshes. J. 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High-Speed, Low-Power and Mid-IR Silicon Photonics Applications

In this book, the first high-speed silicon-organic hybrid (SOH) modulator is demonstrated by exploiting a highly-nonlinear polymer cladding and a silicon waveguide. By using a liquid crystal cladding instead, an ultra-low power phase shifter is obtained. A third type of device is proposed for achieving three-wave mixing on the silicon-organic hybrid (SOH) platform. Finally, new physical constants which describe the optical absorption in charge accumulation/inversion layers in silicon are determined

Toward Adaptation of fNIRS Instrumentation to Airborne Environments

The paper reviews potential applications of functional Near-Infrared Spectroscopy (fNIRS), a well-known medical diagnostic technique, to monitoring the cognitive state of pilots with a focus on identifying ways to adopt this technique to airborne environments. We also discuss various fNIRS techniques and the direction of technology maturation of associated hardware in view of their potential for miniaturization, maximization of data collection capabilities, and user friendliness

Photonic wideband phased array: an optical time steered antenna based on a new true time delay unit

L’attività di ricerca svolta durante il corso di dottorato e descritta dettagliatamente all’interno della tesi è stata diretta al progetto di una innovativa rete ottica di formazione del fascio per antenne a schiera a banda larga esenti dal fenomeno del beam squint. La rete di formazione del fascio proposta è basata sull’utilizzo di un chip ottico integrato modulare che consente di realizzare il True Time Delay implementando switched delay lines. Le caratteristiche del sistema ne consentono l’utilizzo in architetture ad array e a subarray, e la sua modularità rende possibile, in principio, il pilotaggio del sistema radiante, integrando in un unico componente le linee di ritardo di ciascun elemento della schiera. Nella sua prima parte la tesi di dottorato introduce alle antenne ad alte prestazioni richieste dalle moderne applicazioni, focalizzando l’attenzione sui Phased Array, sistemi radianti destinati a svolgere un ruolo di primo piano grazie alla loro flessibilità e potenzialità. Un’analisi ragionata delle soluzioni proposte in letteratura viene, quindi, proposta al fine di evidenziare i principi di funzionamento e le principali problematiche connesse all’implementazione di reti ottiche di formazione del fascio. Inoltre, vengono descritte e discusse le architetture ottiche utilizzate sia per il controllo della fase che per il controllo del ritardo. Successivamente viene presentata la nuova unità ottica integrata di tipo True Time Delay. Le configurazioni di utilizzo del chip ottico studiate e messe a punto durante gli anni del corso di dottorato vengono presentate nel dettaglio, chiarendo le scelte e le strategie di progetto utilizzate in modo da ottimizzare le prestazioni del sistema. Viene presentato il progetto di un prototipo di antenna a schiera basato sul nuovo modulo True Time Delay e un modello accurato dell’intero sistema, implementato allo scopo di verificare il funzionamento dell’antenna e determinarne le prestazioni. Il modello sviluppato tiene in conto delle reali caratteristiche dei dispositivi disponibili in commercio da utilizzarsi all’interno della rete e del sistema radiante, degli inevitabili errori realizzativi relativi a ciascun componente e delle caratteristiche peculiari del nuovo modulo di ritardo. Per compensare gli effetti degli errori suddetti è stata prevista all’interno della rete un’unità di compensazione. Per rendere semplice ed efficace determinarne i parametri è stato sviluppato un algoritmo evolutivo capace di sfruttare al meglio le potenzialità dell’unità così da evitare inutili complessità. Infine, viene proposta una nuova architettura, interamente ottica, di una rete di formazione del fascio per antenne a schiera capaci di irradiare sia fasci somma che fasci differenza beam squint free

Power system applications of fiber optics

Power system applications of optical systems, primarily using fiber optics, are reviewed. The first section reviews fibers as components of communication systems. The second section deals with fiber sensors for power systems, reviewing the many ways light sources and fibers can be combined to make measurements. Methods of measuring electric field gradient are discussed. Optical data processing is the subject of the third section, which begins by reviewing some widely different examples and concludes by outlining some potential applications in power systems: fault location in transformers, optical switching for light fired thyristors and fault detection based on the inherent symmetry of most power apparatus. The fourth and final section is concerned with using optical fibers to transmit power to electric equipment in a high voltage situation, potentially replacing expensive high voltage low power transformers. JPL has designed small photodiodes specifically for this purpose, and fabricated and tested several samples. This work is described

LASER Tech Briefs, Spring 1994

Topics in this Laser Tech Brief include: Electronic Components and Circuits. Electronic Systems, Physical Sciences, Materials, Mechanics, Fabrication Technology, and books and reports

Comparative analysis of long-haul system based on SSB modulation utilising dual parallel Mach–Zehnder modulators

In this paper, we have proposed a long-haul optical transmission system, based on a single sideband (SSB) modulation scheme. Analytical and simulation models have been developed, optimised and demonstrated for the proposed SSB system configurations. The SSB modulation scheme was proposed to overcome dispersion in the fibre. We have shown that the related link losses can be minimized by increasing the quality of the optical signal at the modulation. We have optimised the radio over fibre configuration scheme based on dual parallel dual drive Mach–Zehnder Modulator, thereby increasing transmission length of the fibre. With the proposed SSB, by suppressing some of the harmonics and cancelling one of the sidebands, we have halved the RF power fading and interference. The developed analytical (theoretical/mathematical) model agrees very well with the simulation results using two (both) different commercial simulation tools. The optical signal is boosted while minimizing the number of repeaters. We report a SSB configuration, compensation and amplification with individual spans of 150 km, by extending the length of the link up to 3250 km. The proposed system configuration exhibits high performance with less complexity and lower cost