Photonic Frequency Conversion of OFDM Microwave Signals in a Wavelength-Scale Optomechanical Cavity

[EN] Optomechanical (OM) cavities enable coupling of near-infrared light and GHz-frequency acoustic waves in wavelength-scale volumes. When driven in the phonon lasing regime, an OM cavity can perform simultaneously as a nonlinear mixer and a local oscillator¿at integer multiples of the mechanical resonance frequency¿in the optical domain. In this work, this property is used to demonstrate all-optical frequency down- and up-conversion of MHz-bandwidth orthogonal frequency division multiplexed signals compliant with the IEEE 802.16e WiMAX wireless standard at microwave frequencies. To this end, a silicon OM crystal cavity (OMCC), supporting a breathing-like mechanical resonance at fm ¿3.9 GHz and having a foot-print ¿ 10 um^2, which yields frequency conversion efficiencies better than ¿17 dB in both down- and up-conversion processes at mW-scale driving power, is employed. This work paves the way toward the application of OMCCs in low-power all-photonic processing of digitally modulated microwave signals in miniaturized silicon photonics chips.The authors acknowledge funding from the H2020 Future and Emerging Technologies program (projects PHENOMEN 713450 and SIOMO 945915); the Spanish State Research Agency (PGC2018-094490-BC21, PID2019-106163RJ-I00/AEI/10.13039/501100011033 MULTICORE+ and MCIU/AEI/FEDER UE RTI2018-101296-B-I00 MULTI-BEAM5G); Generalitat Valenciana (PPC/2021/042, BEST/2020/178, PROMETEO/2019/123 and IDIFEDER/2018/033); and the UPV Programa de Ayudas de Investigacion y Desarrollo (PAID-01-16).Mercadé-Morales, L.; Morant, M.; Griol Barres, A.; Llorente, R.; Martínez, A. (2021). Photonic Frequency Conversion of OFDM Microwave Signals in a Wavelength-Scale Optomechanical Cavity. Laser & Photonics Review. 15(11):1-8. https://doi.org/10.1002/lpor.20210017518151

Vertical Engineering for Large Brillouin Gain in Unreleased Silicon-Based Waveguides

[EN] Strong acousto-optic interaction in high-index waveguides and cavities generally requires the releasing of the high-index core to avoid mechanical leakage into the underlying low-index substrate. This complicates fabrication, limits thermalization, reduces the mechanical robustness, and hinders large-area optomechanical devices on a single chip. Here, we overcome this limitation by employing vertical photonic-phononic engineering to drastically reduce mechanical leakage into the cladding by adding a pedestal with specific properties between the core and the cladding. We apply this concept to a silicon-based platform, due to the remarkable properties of silicon to enhance optomechanical interactions and the technological relevance of silicon devices in multiple applications. Specifically, the insertion of a thick silicon nitride layer between the silicon guiding core and the silica substrate contributes to reducing gigahertz-frequency phonon leakage while enabling large values of the Brillouin gain in an unreleased platform. We numerically obtain values of the Brillouin gain around 300 ( W m ) ¿ 1 for different configurations, which could be further increased by operation at cryogenic temperatures. These values should enable Brillouin-related phenomena in centimeter-scale waveguides or in more compact ring resonators. Our findings could pave the way toward large-area unreleased-cavity and waveguide optomechanics on silicon and other high-index photonic technologies.This work was supported by the European Commission (PHENOMEN Grant No. H2020-EU-713450), the Universitat Politecnica de Valencia (Grant No. PAID-01-169), the Ministerio de Ciencia, Innovacion y Universidades (Grants No. PGC2018-094490-B and No. PRX18/00126), and the Generalitat Valenciana (Grant No. PROMETEO/2019/123)Mercadé-Morales, L.; Korovin, AV.; Pennec, Y.; Ahopelto, J.; Djafari-Rouhani, B.; Martínez Abietar, AJ. (2021). Vertical Engineering for Large Brillouin Gain in Unreleased Silicon-Based Waveguides. Physical Review Applied. 15(3):1-9. https://doi.org/10.1103/PhysRevApplied.15.0340211915

Exotic nanophotonics with subwavelength high-index disks

[EN] High-index dielectric disks with subwavelength dimensions seem relatively simple electromagnetic structures. However, they can give rise to exotic phenomena in nanophotonics. Here we show recent findings that show that high-index disks can be used to manipulate light in subwavelength dimensions as a result of Mie and Fabry-Perot resonances. We also propose that such disks can be used for new applications in photonic integrated circuits (PICs) using silicon technology.A. M. acknowledges funding from Generalitat Valenciana (BEST/2020/178, IDIFEDER/2018/033, PPC/2018/002, PROMETEO/2019/123, IDIFEDER/2020/041); Ministerio de Ciencia e Innovación (PGC2018-094490-B-C21, ICTS-2017- 28-UPV-9); European Commission, H2020 Future and Emerging Technologies (713450, 829067).Díaz-Escobar, E.; Pinilla-Cienfuegos, E.; Barreda, ÁI.; Mercadé-Morales, L.; Griol Barres, A.; Martínez, A. (2021). Exotic nanophotonics with subwavelength high-index disks. Íñigo Cuiñas Gómez. 1-4. http://hdl.handle.net/10251/1910791

Hybrid photonic-plasmonic cavities based on the nanoparticle-on-a-mirror configuration

[EN] Hybrid photonic-plasmonic cavities have emerged as a new platform to increase light-matter interaction capable to enhance the Purcell factor in a singular way not attainable with either photonic or plasmonic cavities separately. In the hybrid cavities proposed so far, the plasmonic element is usually a metallic bow-tie antenna, so the plasmonic gap-defined by lithography-is limited to minimum values of several nanometers. Nanoparticle-on-a-mirror (NPoM) cavities are far superior to achieve the smallest possible mode volumes, as plasmonic gaps smaller than 1 nm can be created. Here, we design a hybrid cavity that combines an NPoM plasmonic cavity and a dielectric-nanobeam photonic crystal cavity operating at transverse-magnetic polarization. The metallic nanoparticle can be placed very close (<1 nm) to the upper surface of the dielectric cavity, which acts as a low-reflectivity mirror. We demonstrate through numerical calculations of the local density of states that this hybrid plasmonic-photonic cavity exhibits quality factors Q above 10(3) and normalized mode volumes V down to 10(-3), thus resulting in high Purcell factors (F-P approximate to 10(5)), while being experimentally feasible with current technology. Our results suggest that hybrid cavities with sub-nanometer gaps should open new avenues for boosting light -matter interaction in nanophotonic systems.Horizon 2020 Framework Programme (829067 THOR); Generalitat Valenciana (PPC/2018/002, PROMETEO/2019/123); Ministerio de Ciencia, Innovacion y Universidades (PGC2018-094490-B, PRX18/00126); Alexander von Humboldt-Stiftung.Barreda, ÁI.; Zapata-Herrera, M.; Palstra, IM.; Mercadé-Morales, L.; Aizpurua, J.; Koenderink, AF.; Martínez Abietar, AJ. (2021). Hybrid photonic-plasmonic cavities based on the nanoparticle-on-a-mirror configuration. Photonics Research. 9(12):2398-2419. https://doi.org/10.1364/PRJ.433761S2398241991

Electron Emission of Pt: Experimental Study and Comparison With Models in the Multipactor Energy Range

"(c) 2016 IEEE. Personal use of this material is permitted. Permission from IEEE must be obtained for all other users, including reprinting/ republishing this material for advertising or promotional purposes, creating new collective works for resale or redistribution to servers or lists, or reuse of any copyrighted components of this work in other works."Experimental data of secondary emission yield (SEY) and electron emission spectra of Pt under electron irradiation for normal incidence and primary energies lower than 1 keV are presented. Several relevant magnitudes, as total SEY, elastic backscattering probability, secondary emission spectrum, and backscattering coefficient, are given for different primary energies. These magnitudes are compared with theoretical or semiempiricalThis work was supported in part by the Ministerio de Economia y Competitividad under Project TEC2013-47037-C5-4-R, and in part by MICIIN through the Space Programme under Project AYA2012-39832-C02-01/02. The review of this paper was arranged by Editor M. Thumm.Bronchalo, E.; Coves, A.; Mata Sanz, R.; Gimeno Martinez, B.; Montero, I.; Galán, L.; Boria Esbert, VE.... (2016). Electron Emission of Pt: Experimental Study and Comparison With Models in the Multipactor Energy Range. IEEE Transactions on Electron Devices. 63(8):3270-3277. https://doi.org/10.1109/TED.2016.2580199S3270327763

Nanocrystalline silicon optomechanical cavities

"© 2018 Optical Society of America. One print or electronic copy may be made for personal use only. Systematic reproduction and distribution, duplication of any material in this paper for a fee or for commercial purposes, or modifications of the content of this paper are prohibited"[EN] Silicon on insulator photonics has offered a versatile platform for the recent development of integrated optomechanical circuits. However, there are some constraints such as the high cost of the wafers and limitation to a single physical device level. In the present work we investigate nanocrystalline silicon as an alternative material for optomechanical devices. In particular we demonstrate that optomechanical crystal cavities fabricated of nanocrystalline silicon have optical and mechanical properties enabling non-linear dynamical behaviour and effects such as thermo-optic/free-carrier-dispersion self-pulsing, phonon lasing and chaos, all at low input laser power and with typical frequencies as high as 0.3 GHz. (C) 2018 Optical Society of America under the terms of the OSA Open Access Publishing AgreementEuropean Commission project PHENOMEN (H2020-EU-713450), MINECO Severo Ochoa Excellence program (SEV-2013-0295), MINECO (FIS2015-70862-P, RYC-2014-15392) and CERCA Programme/Generalitat de Catalunya.Navarro-Urrios, D.; Capuj, N.; Maire, J.; Colombano, M.; Jaramillo-Fernandez, J.; Chavez-Angel, E.; Martín-Rodríguez, LL.... (2018). Nanocrystalline silicon optomechanical cavities. Optics Express. 26(8):9829-9839. https://doi.org/10.1364/OE.26.009829S98299839268Kippenberg, T. J., & Vahala, K. J. (2008). Cavity Optomechanics: Back-Action at the Mesoscale. Science, 321(5893), 1172-1176. doi:10.1126/science.1156032Aspelmeyer, M., Kippenberg, T. J., & Marquardt, F. (2014). Cavity optomechanics. Reviews of Modern Physics, 86(4), 1391-1452. doi:10.1103/revmodphys.86.1391Navarro-Urrios, D., Capuj, N. E., Gomis-Bresco, J., Alzina, F., Pitanti, A., Griol, A., … Sotomayor Torres, C. M. (2015). A self-stabilized coherent phonon source driven by optical forces. Scientific Reports, 5(1). doi:10.1038/srep15733Navarro-Urrios, D., Capuj, N. E., Colombano, M. F., García, P. D., Sledzinska, M., Alzina, F., … Sotomayor-Torres, C. M. (2017). Nonlinear dynamics and chaos in an optomechanical beam. Nature Communications, 8(1). doi:10.1038/ncomms14965Leijssen, R., La Gala, G. R., Freisem, L., Muhonen, J. T., & Verhagen, E. (2017). Nonlinear cavity optomechanics with nanomechanical thermal fluctuations. Nature Communications, 8(1). doi:10.1038/ncomms16024Gil-Santos, E., Labousse, M., Baker, C., Goetschy, A., Hease, W., Gomez, C., … Favero, I. (2017). Light-Mediated Cascaded Locking of Multiple Nano-Optomechanical Oscillators. Physical Review Letters, 118(6). doi:10.1103/physrevlett.118.063605Shah, S. Y., Zhang, M., Rand, R., & Lipson, M. (2015). Master-Slave Locking of Optomechanical Oscillators over a Long Distance. Physical Review Letters, 114(11). doi:10.1103/physrevlett.114.113602Weis, S., Rivière, R., Deléglise, S., Gavartin, E., Arcizet, O., Schliesser, A., & Kippenberg, T. J. (2010). Optomechanically Induced Transparency. Science, 330(6010), 1520-1523. doi:10.1126/science.1195596Verhagen, E., Deléglise, S., Weis, S., Schliesser, A., & Kippenberg, T. J. (2012). Quantum-coherent coupling of a mechanical oscillator to an optical cavity mode. Nature, 482(7383), 63-67. doi:10.1038/nature10787Tomes, M., & Carmon, T. (2009). Photonic Micro-Electromechanical Systems Vibrating atX-band (11-GHz) Rates. Physical Review Letters, 102(11). doi:10.1103/physrevlett.102.113601Thompson, J. D., Zwickl, B. M., Jayich, A. M., Marquardt, F., Girvin, S. M., & Harris, J. G. E. (2008). Strong dispersive coupling of a high-finesse cavity to a micromechanical membrane. Nature, 452(7183), 72-75. doi:10.1038/nature06715Eichenfield, M., Chan, J., Camacho, R. M., Vahala, K. J., & Painter, O. (2009). Optomechanical crystals. Nature, 462(7269), 78-82. doi:10.1038/nature08524Chan, J., Alegre, T. P. M., Safavi-Naeini, A. H., Hill, J. T., Krause, A., Gröblacher, S., … Painter, O. (2011). Laser cooling of a nanomechanical oscillator into its quantum ground state. Nature, 478(7367), 89-92. doi:10.1038/nature10461Safavi-Naeini, A. H., Alegre, T. P. M., Chan, J., Eichenfield, M., Winger, M., Lin, Q., … Painter, O. (2011). Electromagnetically induced transparency and slow light with optomechanics. Nature, 472(7341), 69-73. doi:10.1038/nature09933Pennec, Y., Laude, V., Papanikolaou, N., Djafari-Rouhani, B., Oudich, M., El Jallal, S., … Martínez, A. (2014). Modeling light-sound interaction in nanoscale cavities and waveguides. Nanophotonics, 3(6), 413-440. doi:10.1515/nanoph-2014-0004Davanço, M., Ates, S., Liu, Y., & Srinivasan, K. (2014). Si3N4 optomechanical crystals in the resolved-sideband regime. Applied Physics Letters, 104(4), 041101. doi:10.1063/1.4858975Balram, K. C., Davanço, M. I., Song, J. D., & Srinivasan, K. (2016). Coherent coupling between radiofrequency, optical and acoustic waves in piezo-optomechanical circuits. Nature Photonics, 10(5), 346-352. doi:10.1038/nphoton.2016.46Bochmann, J., Vainsencher, A., Awschalom, D. D., & Cleland, A. N. (2013). Nanomechanical coupling between microwave and optical photons. Nature Physics, 9(11), 712-716. doi:10.1038/nphys2748Xiong, C., Pernice, W. H. P., Sun, X., Schuck, C., Fong, K. Y., & Tang, H. X. (2012). Aluminum nitride as a new material for chip-scale optomechanics and nonlinear optics. New Journal of Physics, 14(9), 095014. doi:10.1088/1367-2630/14/9/095014Gomis-Bresco, J., Navarro-Urrios, D., Oudich, M., El-Jallal, S., Griol, A., Puerto, D., … Torres, C. M. S. (2014). A one-dimensional optomechanical crystal with a complete phononic band gap. Nature Communications, 5(1). doi:10.1038/ncomms5452Heck, M. J. R., Bauters, J. F., Davenport, M. L., Spencer, D. T., & Bowers, J. E. (2014). Ultra-low loss waveguide platform and its integration with silicon photonics. Laser & Photonics Reviews, 8(5), 667-686. doi:10.1002/lpor.201300183Solehmainen, K., Aalto, T., Dekker, J., Kapulainen, M., Harjanne, M., Kukli, K., … Leskela, M. (2005). Dry-etched silicon-on-insulator waveguides with low propagation and fiber-coupling losses. Journal of Lightwave Technology, 23(11), 3875-3880. doi:10.1109/jlt.2005.857750Sekoguchi, H., Takahashi, Y., Asano, T., & Noda, S. (2014). Photonic crystal nanocavity with a Q-factor of ~9 million. Optics Express, 22(1), 916. doi:10.1364/oe.22.000916Almeida, V. R., Barrios, C. A., Panepucci, R. R., & Lipson, M. (2004). All-optical control of light on a silicon chip. Nature, 431(7012), 1081-1084. doi:10.1038/nature02921Narayanan, K., & Preble, S. F. (2010). Optical nonlinearities in hydrogenated-amorphous silicon waveguides. Optics Express, 18(9), 8998. doi:10.1364/oe.18.008998Preston, K., Dong, P., Schmidt, B., & Lipson, M. (2008). High-speed all-optical modulation using polycrystalline silicon microring resonators. Applied Physics Letters, 92(15), 151104. doi:10.1063/1.2908869Wang, K.-Y., & Foster, A. C. (2012). Ultralow power continuous-wave frequency conversion in hydrogenated amorphous silicon waveguides. Optics Letters, 37(8), 1331. doi:10.1364/ol.37.001331Matres, J., Ballesteros, G. C., Gautier, P., Fédéli, J.-M., Martí, J., & Oton, C. J. (2013). High nonlinear figure-of-merit amorphous silicon waveguides. Optics Express, 21(4), 3932. doi:10.1364/oe.21.003932Waldow, M., Plötzing, T., Gottheil, M., Först, M., Bolten, J., Wahlbrink, T., & Kurz, H. (2008). 25ps all-optical switching in oxygen implanted silicon-on-insulator microring resonator. Optics Express, 16(11), 7693. doi:10.1364/oe.16.007693Wang, K.-Y., Petrillo, K. G., Foster, M. A., & Foster, A. C. (2012). Ultralow-power all-optical processing of high-speed data signals in deposited silicon waveguides. Optics Express, 20(22), 24600. doi:10.1364/oe.20.024600Ylönen, M., Torkkeli, A., & Kattelus, H. (2003). In situ boron-doped LPCVD polysilicon with low tensile stress for MEMS applications. Sensors and Actuators A: Physical, 109(1-2), 79-87. doi:10.1016/j.sna.2003.09.017Theodorakos, I., Zergioti, I., Vamvakas, V., Tsoukalas, D., & Raptis, Y. S. (2014). Picosecond and nanosecond laser annealing and simulation of amorphous silicon thin films for solar cell applications. Journal of Applied Physics, 115(4), 043108. doi:10.1063/1.4863402Navarro-Urrios, D., Gomis-Bresco, J., El-Jallal, S., Oudich, M., Pitanti, A., Capuj, N., … Sotomayor Torres, C. M. (2014). Dynamical back-action at 5.5 GHz in a corrugated optomechanical beam. AIP Advances, 4(12), 124601. doi:10.1063/1.4902171Barclay, P. E., Srinivasan, K., & Painter, O. (2005). Nonlinear response of silicon photonic crystal micresonators excited via an integrated waveguide and fiber taper. Optics Express, 13(3), 801. doi:10.1364/opex.13.000801Cuffe, J., Ristow, O., Chávez, E., Shchepetov, A., Chapuis, P.-O., Alzina, F., … Sotomayor Torres, C. M. (2013). Lifetimes of Confined Acoustic Phonons in Ultrathin Silicon Membranes. Physical Review Letters, 110(9). doi:10.1103/physrevlett.110.095503Volklein, F., & Balles, H. (1992). A Microstructure For Measurement Of Thermal Conductivity Of Polysilicon Thin Films. 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Study of the Secondary Electron Yield in Dielectrics Using Equivalent Circuital Models

© 2018 IEEE. Personal use of this material is permitted. Permissíon from IEEE must be obtained for all other uses, in any current or future media, including reprinting/republishing this material for advertisíng or promotional purposes, creating new collective works, for resale or redistribution to servers or lists, or reuse of any copyrighted component of this work in other works.[EN] Secondary electron emission has an important role on the triggering of the multipactor effect; therefore, its study and characterization are essential in radio-frequency waveguide applications. In this paper, we propose a theoretical model, based on equivalent circuit models, to properly understand charging and discharging processes that occur in dielectric samples under electron irradiation for secondary electron emission characterization. Experimental results obtained for Pt, Si, GaS, and Teflon samples are presented to verify the accuracy of the proposed model. Good agreement between theory and experiments has been found.The authors would like to thank the European High Power Space Materials Laboratory for its contribution-a laboratory funded by the European Regional Development Fund-a way of making Europe. Many thanks to the University of Valencia (Spain) for supporting this research activity with the internal program "Assistance for temporary stays of invited researchers within the framework of the Subprogramme Attraction of Talent 2015".Bañón, D.; Socuellamos, JM.; Mata-Sanz, R.; Mercadé-Morales, L.; Gimeno Martínez, B.; Boria Esbert, VE.; Raboso García-Baquero, D.... (2018). Study of the Secondary Electron Yield in Dielectrics Using Equivalent Circuital Models. IEEE Transactions on Plasma Science. 46(4):859-867. https://doi.org/10.1109/TPS.2018.2809602S85986746

Expression of CD20 after viral reactivation renders HIV-reservoir cells susceptible to Rituximab

Rituximab; Viral reactivation; CD20Rituximab; Reactivació viral; CD20Rituximab; Reactivación viral; CD20The identification of exclusive markers to target HIV-reservoir cells will represent a significant advance in the search for therapies to cure HIV. Here, we identify the B lymphocyte antigen CD20 as a marker for HIV-infected cells in vitro and in vivo. The CD20 molecule is dimly expressed in a subpopulation of CD4-positive (CD4+) T lymphocytes from blood, with high levels of cell activation and heterogeneous memory phenotypes. In lymph node samples from infected patients, CD20 is present in productively HIV-infected cells, and ex vivo viral infection selectively upregulates the expression of CD20 during early infection. In samples from patients on antiretroviral therapy (ART) this subpopulation is significantly enriched in HIV transcripts, and the anti-CD20 monoclonal antibody Rituximab induces cell killing, which reduces the pool of HIV-expressing cells when combined with latency reversal agents. We provide a tool for targeting this active HIV-reservoir after viral reactivation in patients while on ART.This study was supported by the American National Institutes of Health (grant R21AI118411 to M.B.), the Spanish Secretariat of Science and Innovation and FEDER funds (grant SAF2015-67334-R [MINECO/FEDER]), the Spanish "Ministerio de Economia y Competitividad, Instituto de Salud Carlos III" (ISCIII, PI17/01470), GeSIDA and the Spanish AIDS network Red Tematica Cooperativa de Investigacion en SIDA (RD16/0025/0007). M.B. is supported by the Miguel Servet program funded by the Spanish Health Institute Carlos III (CP17/00179). M.G. is supported by the "Pla estrategic de recerca i innovacio en salut" (PERIS), from the Catalan Government

TFG 2014/2015

Amb aquesta publicació, EINA, Centre universitari de Disseny i Art adscrit a la Universitat Autònoma de Barcelona, dóna a conèixer el recull dels Treballs de Fi de Grau presentats durant el curs 2014-2015. Voldríem que un recull com aquest donés una idea més precisa de la tasca que es realitza a EINA per tal de formar nous dissenyadors amb capacitat de respondre professionalment i intel·lectualment a les necessitats i exigències de la nostra societat. El treball formatiu s’orienta a oferir resultats que responguin tant a paràmetres de rigor acadèmic i capacitat d’anàlisi del context com a l’experimentació i la creació de nous llenguatges, tot fomentant el potencial innovador del disseny.Con esta publicación, EINA, Centro universitario de diseño y arte adscrito a la Universidad Autónoma de Barcelona, da a conocer la recopilación de los Trabajos de Fin de Grado presentados durante el curso 2014-2015. Querríamos que una recopilación como ésta diera una idea más precisa del trabajo que se realiza en EINA para formar nuevos diseñadores con capacidad de responder profesional e intelectualmente a las necesidades y exigencias de nuestra sociedad. El trabajo formativo se orienta a ofrecer resultados que respondan tanto a parámetros de rigor académico y capacidad de análisis, como a la experimentación y la creación de nuevos lenguajes, al tiempo que se fomenta el potencial innovador del diseño.With this publication, EINA, University School of Design and Art, affiliated to the Autonomous University of Barcelona, brings to the public eye the Final Degree Projects presented during the 2014-2015 academic year. Our hope is that this volume might offer a more precise idea of the task performed by EINA in training new designers, able to speak both professionally and intellectually to the needs and demands of our society. The educational task is oriented towards results that might respond to the parameters of academic rigour and the capacity for contextual analysis, as well as to considerations of experimentation and the creation of new languages, all the while reinforcing design’s innovative potential

Phonons Manipulation in Silicon Chips Using Cavity Optomechanics

[ES] La optomecánica de cavidades se ocupa de la interacción entre la luz y la materia a través del efecto de presión de radiación cuando las ondas ópticas y mecánicas implicadas están confinadas en una cavidad. En estos sistemas optomecánicos, la interacción entre fotones y fonones da lugar a multitud de fenómenos en función de las condiciones en las que se excita el sistema. En particular, se pueden obtener dos regímenes distintos en los que se puede, o bien absorber fonones (denominado como enfriamiento de la cavidad), o bien éstos se pueden amplificar (régimen conocido como calentamiento de la cavidad). El primer régimen puede usarse, por ejemplo, para reducir la ocupación térmica del sistema y se usa comúnmente para aplicaciones relativas al procesado de información cuántica. Sin embargo, la amplificación de fonones, que puede ser desarrollada a temperatura ambiente, ha permitido conseguir alcanzar incluso las condiciones necesarias para obtener láseres de fonones, lo cual permite poder usar esta característica como elemento de referencia en aplicaciones relativas al procesado de señales de radiofrecuencia (RF). En esta tesis se aborda el confinamiento simultáneo y la interacción de fotones y fonones en estructuras periódicas y en guías no suspendidas desarrolladas en sistemas CMOS compatibles basados en tecnología de silicio. A través del estudio experimental de estas estructuras periódicas, hemos demostrado que las cavidades optomecánicas pueden actuar como elementos clave en el dominio de la fotónica de microondas, donde todo el procesado de la información puede ser realizado en el dominio óptico a través de la manipulación de fonones en este sistema. En particular, mostramos que un solo oscilador optomecánico puede actuar tanto como un oscilador local y un mezclador de RF, y éste puede operar como un conversor de frecuencias de señales de cadenas de datos reales. Para mejorar esta funcionalidad, también se demuestra que es posible obtener tanto peines de frecuencias ópticos así como múltiples modos mecánicos confinados, aumentando así su rendimiento. Por otro lado, con el objetivo de poder solventar las posibles limitaciones de estos sistemas, en esta tesis también se exploran diferentes configuraciones que permiten la interacción acusto-óptica simultánea en la misma estructura. Específicamente, se analiza la interacción optomecánica en discos de alto índice que soportan estados cuasi-ligados en el continuo así como una propuesta de guías no suspendidas que soportan altas ganancias de Brillouin. Este último estudio debería permitir el desarrollo de sistemas optomecánicos no suspendidos donde el problema de la pérdida de fonones hacia el sustrato se resuelva, hecho que permitiría enormemente simplificar la fabricación de estos sistemas optomecánicos en chips de silicio así como su uso en múltiples aplicaciones.[CA] L'optomecànica de cavitats s'ocupa de la interacció entre la llum i la matèria a través de l'efecte de pressió de radiació quan les ones òptiques i mecàniques implicades estan confinades en una cavitat. En aquests sistemes optomecànics, la interacció entre fotons i fonons dona lloc a multitud de fenòmens en funció de les condicions de les condicions en les quals s'excita el sistema. En particular, es poden obtindre dos règims diferents en els quals es pot, o bé, absorbir fonons (denominat com a refredament de la cavitat), o bé, es poden amplificar (règim conegut com a calfament de la cavitat). El primer règim pot usar-se, per exemple, per a reduir l'ocupació tèrmica del sistema i s'usa comunament per a aplicacions relatives al processament d'informació quàntica. No obstant això, l'amplificació de fonons, que pot ser desenvolupada a temperatura ambient, ha permés aconseguir fins i tot les condicions necessàries per a obtindre làsers de fonons, la qual cosa permet poder usar aquesta característica com a element de referència en aplicacions relatives al processament de senyals de radiofreqüència (RF). En aquesta tesi s'aborda el confinament simultani i la interacció de fotons i fonons en estructures periòdiques i en guies no suspeses en sistemes CMOS compatibles basats en tecnologia de silici. A través de l'estudi experimental d'aquestes estructures periòdiques, hem demostrat que les cavitats optomecàniques poden actuar com a elements clau en el domini de la fotònica de microones, on tot el processament de la informació pot ser realitzat en el domini òptic a través de la manipulació de fonons en aquest sistema. En particular, vam mostrar que només un oscil·lador optomecànic pot actuar tant com un oscil·lador local i un mesclador de RF, i aquest pot operar com un convertidor de freqüències de senyals de cadenes de dades reals. Per a millorar aquesta funcionalitat, també es demostra que és possible obtindre tant tren de freqüències òptics així com múltiples modes mecànics confinats, augmentant així el seu rendiment. D'altra banda, amb l'objectiu de poder solucionar les possibles limitacions d'aquests sistemes, en aquesta tesi també s'exploren diferents configuracions que permeten la interacció acusto-òptica simultània en la mateixa estructura. Específicament, s'analitza la interacció optomecànica en discos d'alt índex que suporten estats quasi-lligats en el continu així com una proposta de guies no suspeses que suporten altes ganancies de Brillouin. Aquest últim estudi hauria de permetre el desenvolupament de sistemes optomecànics no suspesos on el problema de la pèrdua de fonons cap al substrat es resolga, fet que permetria enormement simplificar la fabricació d'aquests sistema optomecànics en xips de silici així com el seu ús en diverses aplicacions.[EN] Cavity optomechanics deals with the interaction of light and matter through the radiation pressure effect, when the involved optical and mechanical waves are confined in a cavity. In optomechanical systems, photon and phonon interaction give rise to a plethora of phenomena as a function of the driving conditions of the system. Relative to that, two distinctive regimes can be obtained which enable either the absorption of phonons (cavity cooling) or their amplification (cavity heating). The first regime can be used to reduce the thermal occupancy of the system and it is commonly used for quantum processing information applications. However, the amplification of phonons, which can be performed at room temperature, has enabled to even reach phonon lasing conditions, a feature that could be used as a reference element for RF processing applications. In this thesis, we address the simultaneous confinement and interaction of photons and phonons in periodic structures and unreleased waveguides on CMOS-compatible silicon-based technology. Throughout the experimental study of those periodic structures, we demonstrate that optomechanical cavities can perform as key blocks in the microwave photonics domain where all the information processing can be performed in the optical domain through phonon manipulation. In particular, we show that a single optomechanical oscillator can perform as both a local oscillator and an RF mixer, and it can operate as a frequency-converted of real data stream signals. To improve its performance, it is also demonstrated that optical frequency combs can be obtained by means of this system and multiple mechanical mode confinement can also be achieved, thus improving the functionality of the system. On the other hand, in order to fulfill the possible limitations of those systems, we explore different configurations enabling the simultaneous acousto-optic interaction together into the same structure. Especially, optomechanical interaction in high-index disks supporting quasi-bound states in the continuum is addressed, as well as a proposal of unreleased waveguides supporting strong Brillouin gains is also reported. The last one should lead to unreleased optomechanical interacting systems where the issue of phonon leakage into the substrate is solved, which could enormously simplify the fabrication of optomechanical systems in silicon chips as well as their practical use in multiple applications.This work has been carried out under the framework of the H2020 FET-Open EU project PHENOMEN. This Thesis was also supported by the Programa de Ayudas de Investigación y Desarrollo (PAID-01-16) de la Universitat Politècnica de ValènciaMercadé Morales, L. (2021). Phonons Manipulation in Silicon Chips Using Cavity Optomechanics [Tesis doctoral]. Universitat Politècnica de València. https://doi.org/10.4995/Thesis/10251/171461TESI