Coupling techniques between dielectric waveguides and planar photonic crystals

El objetivo de esta tesis es la investigación de estructuras y técnicas de acoplo para minimizar las pérdidas de acoplo entre guías dieléctricas y cristales fotónicos planares. En primer lugar se ha estudiado el modelado del acoplo entre guías dieléctricas y guías en cristal fotónico así como la influencia de los principales parámetros del cristal en la eficiencia de acoplo. Se han obtenido expresiones cerradas para las matrices de reflexión y transmisión que caracterizan totalmente el scattering que ocurre en el interfaz formado entre una guía dieléctrica y una guía en cristal fotónico. A continuación y con el fin de mejorar la eficiencia de acoplo desde guías dieléctrica de anchura arbitraria, se ha propuesto como contribución original una técnica de acoplo basada en la introducción de defectos puntuales en el interior de una estructura de acoplo tipo cuña realizada en el cristal fotónico. Diferentes soluciones, incluida los algoritmos genéticos, han sido propuestas con el objetivo de conseguir el diseño óptimo de la configuración de defectos. Una vez conseguido un acoplo eficiente desde guías dieléctricas a guías en cristal fotónico, se ha investigado el acoplo en guías de cavidades acopladas. Como contribución original se ha propuesto una técnica de acoplo basada en la variación gradual del radio de los defectos situados entre cavidades adyacentes. Además, se ha realizado un riguroso análisis en el dominio del tiempo y la frecuencia de la propagación de pulsos en guías acopladas de longitud finita. Dicho estudio ha tenido como objetivo la caracterización de la influencia de la eficiencia del acoplo en los parámetros del pulso. Finalmente, se han presentado los procesos de fabricación y resultados experimentales de las estructuras de acoplo propuestas.Sanchis Kilders, P. (2005). Coupling techniques between dielectric waveguides and planar photonic crystals [Tesis doctoral no publicada]. Universitat Politècnica de València. https://doi.org/10.4995/Thesis/10251/1854Palanci

Functional oxides in photonic integrated devices

[EN] At the end of a rush lasting over half a century, in which CMOS technology has been experiencing a constant and breathtaking increase of device speed and density, Moore¿s law is approaching the insurmountable barrier given by the ultimate atomic nature of matter. A major challenge for 21st century scientists is finding novel strategies, concepts and materials for replacing silicon-based CMOS semiconductor technologies and guaranteeing a continued and steady technological progress in next decades. Among the materials classes candidate to contribute to this momentous challenge, oxide films and heterostructures are a particularly appealing hunting ground. The vastity, intended in pure chemical terms, of this class of compounds, the complexity of their correlated behaviour, and the wealth of functional properties they display, has already made these systems the subject of choice, worldwide, of a strongly networked, dynamic and interdisciplinary research community.Gervasi Herranz acknowledges financial support from MAT2014-56063-C2-1-R and Severo Ochoa SEV-2015-0496 Projects, and the Generalitat de Catalunya (2014 SGR 734Project). Pablo Sanchis acknowledges financial support from TEC2016-76849 and FP7-ICT-2013-11-619456 SITOGA.Herranz, G.; Sanchis Kilders, P. (2019). Functional oxides in photonic integrated devices. Applied Surface Science. 482:52-55. https://doi.org/10.1016/j.apsusc.2019.03.312525548

Enhanced Pockels effect in strained silicon by means of a SiGe/Si/SiGe slot structure

[EN] A slot waveguide structure made of a SiGe/Si/SiGe heterojunction is proposed to enhance Pockels effect in strained silicon. The strain is applied via lattice mismatch between layers, while the slot configuration optimizes the overlap between the optical and electric field inside the strained silicon.Funding from projects TEC2016-76849 (MINECO/FEDER, UE) and PROMETEO/2019/123 (Generalitat Valenciana) is acknowledged. Irene Olivares acknowledges the UPV for funding her research staff training (FPI) grant.Olivares-Sánchez-Mellado, I.; Sanchis Kilders, P. (2020). Enhanced Pockels effect in strained silicon by means of a SiGe/Si/SiGe slot structure. IEEE. 1-2. https://doi.org/10.1109/IPC47351.2020.9252351S1

A SiGe Slot Approach for Enhancing Strain Induced Pockels Effect in the Mid-IR Range

[EN] Strained silicon was proposed more than a decade ago promising to revolutionize the silicon photonics field by allowing efficient modulation in this platform. Despite all the efforts, still rather low chi(2) values have been measured in strained silicon devices. In addition, the way of applying strain has not barely changed since the concept was proposed, usually consisting on a silicon waveguide covered by a stressor material such as silicon nitride. In this letter, a SiGe slot approach is explored as a different route to enhance the strain induced Pockels effect in the mid-IR range. Such approach would allow effective index change values which are near to 10(-4) and improve the values expected for the most common silicon - silicon nitride structure by more than three orders of magnitude.This work was supported in part by the Ministerio de Ciencia e Innovacion under Grant TEC2016-76849 and Grant PID2019-111460GB-I00 and in part by the Generalitat Valenciana under Grant PROMETEO/2019/123.Olivares-Sánchez-Mellado, I.; Sanchis Kilders, P. (2021). A SiGe Slot Approach for Enhancing Strain Induced Pockels Effect in the Mid-IR Range. IEEE Photonics Technology Letters. 33(16):848-851. https://doi.org/10.1109/LPT.2021.3075753848851331

Broadband 8 micrometers long hybrid silicon-plasmonic transverse magnetic-transverse electric converter with losses below 2 dB

This paper was published in Optics Letters and is made available as an electronic reprint with the permission of OSA. The paper can be found at the following URL on the OSA website: http://dx.doi.org/10.1364/OL.38.002842. Systematic or multiple reproduction or distribution to multiple locations via electronic or other means is prohibited and is subject to penalties under lawA novel ultracompact (8 mu m length) hybrid silicon-plasmonic TM-TE converter is reported. The conversion is achieved during a partial power coupling between a waveguide and a hybrid plasmonic parallel waveguide. The impact of different types of metals is also analyzed. At a wavelength of 1.55 mu m, the device has an extinction ratio (ER) of 27.6 dB and insertion loss (IL) of 1.75 dB. Furthermore, an optical bandwidth as large as 100 nm is achieved with ERs higher than 25 dB and ILs below 2 dB. (C) 2013 Optical Society of AmericaThe authors acknowledge funding from TEC2012-38540 LEOMIS and PROMETEO-2010-087. L. Sanchez also acknowledges the Generalitat Valenciana for funding his grant in the context of the VALi+d program.Sánchez Diana, LD.; Sanchis Kilders, P. (2013). Broadband 8 micrometers long hybrid silicon-plasmonic transverse magnetic-transverse electric converter with losses below 2 dB. Optics Letters. 38(15):2842-2845. https://doi.org/10.1364/OL.38.002842S284228453815Jalali, B., & Fathpour, S. (2006). Silicon Photonics. Journal of Lightwave Technology, 24(12), 4600-4615. doi:10.1109/jlt.2006.885782Dionne, J. A., Sweatlock, L. A., Sheldon, M. T., Alivisatos, A. P., & Atwater, H. A. (2010). Silicon-Based Plasmonics for On-Chip Photonics. IEEE Journal of Selected Topics in Quantum Electronics, 16(1), 295-306. doi:10.1109/jstqe.2009.2034983Zhu, S., Lo, G.-Q., & Kwong, D.-L. (2012). Experimental Demonstration of Vertical ${\rm Cu}\hbox{-}{\rm SiO}_{2}\hbox{-}{\rm Si}$ Hybrid Plasmonic Waveguide Components on an SOI Platform. IEEE Photonics Technology Letters, 24(14), 1224-1226. doi:10.1109/lpt.2012.2199979Tobing, L. Y. M., Tjahjana, L., & Hua Zhang, D. (2012). Demonstration of low-loss on-chip integrated plasmonic waveguide based on simple fabrication steps on silicon-on-insulator platform. Applied Physics Letters, 101(4), 041117. doi:10.1063/1.4739523Fedyanin, D. Y., Krasavin, A. V., Arsenin, A. V., & Zayats, A. V. (2012). Surface Plasmon Polariton Amplification upon Electrical Injection in Highly Integrated Plasmonic Circuits. Nano Letters, 12(5), 2459-2463. doi:10.1021/nl300540xAlonso-Ramos, C., Halir, R., Ortega-Moñux, A., Cheben, P., Vivien, L., Molina-Fernández, Í., … Schmid, J. (2012). Highly tolerant tunable waveguide polarization rotator scheme. Optics Letters, 37(17), 3534. doi:10.1364/ol.37.003534Zhang, H., Das, S., Zhang, J., Huang, Y., Li, C., Chen, S., … Thong, J. T. L. (2012). Efficient and broadband polarization rotator using horizontal slot waveguide for silicon photonics. Applied Physics Letters, 101(2), 021105. doi:10.1063/1.4734640Aamer, M., Gutierrez, A. M., Brimont, A., Vermeulen, D., Roelkens, G., Fedeli, J.-M., … Sanchis, P. (2012). CMOS Compatible Silicon-on-Insulator Polarization Rotator Based on Symmetry Breaking of the Waveguide Cross Section. IEEE Photonics Technology Letters, 24(22), 2031-2034. doi:10.1109/lpt.2012.2218593Nakayama, K., Shoji, Y., & Mizumoto, T. (2012). Single Trench SiON Waveguide TE-TM Mode Converter. IEEE Photonics Technology Letters, 24(15), 1310-1312. doi:10.1109/lpt.2012.2202646Komatsu, M., Saitoh, K., & Koshiba, M. (2012). Compact Polarization Rotator Based on Surface Plasmon Polariton With Low Insertion Loss. IEEE Photonics Journal, 4(3), 707-714. doi:10.1109/jphot.2012.2195650Caspers, J. N., Alam, M. Z., & Mojahedi, M. (2012). Compact hybrid plasmonic polarization rotator. Optics Letters, 37(22), 4615. doi:10.1364/ol.37.004615Roberts, S. (1960). Optical Properties of Copper. Physical Review, 118(6), 1509-1518. doi:10.1103/physrev.118.1509Sun, X., Alam, M. Z., Wagner, S. J., Aitchison, J. S., & Mojahedi, M. (2012). Experimental demonstration of a hybrid plasmonic transverse electric pass polarizer for a silicon-on-insulator platform. Optics Letters, 37(23), 4814. doi:10.1364/ol.37.00481

Non-Volatile Photonic Memory Based on a SAHAS Configuration

[EN] The non-volatile memory is a crucial functionality for a wide range of applications in photonic integrated circuits, however, it still poses a challenge in silicon photonic technology. This problem has been overcome in the microelectronic industry by using SONOS (silicon-oxide-nitride-oxide-silicon) memory cells, in which the non-volatility is enabled by a dielectric trapping layer such as silicon nitride. Analogously, in this work, a similar approach in which the nitride has been replaced by a hafnium oxide layer, named as SAHAS configuration, is proposed for enabling a programmable erasable photonic memory fully compatible with the silicon platform. The structure features an efficient performance with writing and erasing times of 100 mu s, retention times over 10 years and energy consumption in the pJ range, which improve the current SONOS or floating gate based photonic approaches that exploit the plasma dispersion effect in silicon. The proposed non-volatile photonic memory device shows an extinction ratio above 12 dB and insertion losses below 1 dB in a compact footprint. In addition, because the memory is optically read, ultrafast access times in the picosecond range are also achieved.This work was supported in part by Ministerio de Economia y Competitividad (MINECO/FEDER, UE) (TEC2016-76849), in part by Generalitat Valenciana (PROMETEO/2019/123), in part by Ministerio de Ciencia e Innovacion (MINECO/FEDER, UE) (PID2019-111460GB-I00, FPU17/04224), and in part by Universitat Politecnica de Valencia (FPI Grant).Olivares-Sánchez-Mellado, I.; Parra Gómez, J.; Sanchis Kilders, P. (2021). Non-Volatile Photonic Memory Based on a SAHAS Configuration. IEEE Photonics Journal. 13(2):1-9. https://doi.org/10.1109/JPHOT.2021.3060144S1913

On the influence of interface charging dynamics and stressing conditions in strained silicon devices

[EN] The performance of strained silicon devices based on the deposition of a top silicon nitride layer with high stress have been thoroughly analyzed by means of simulations and experimental results. Results clearly indicate that the electro-optic static response is basically governed by carrier efects. A frst evidence is the appearance of a variable optical absorption with the applied voltage that should not occur in case of having a purely electro-optic Pockels efect. However, hysteresis and saturation efects are also observed. We demonstrate that such efects are mainly due to the carrier trapping dynamics at the interface between the silicon and the silicon nitride and their infuence on the silicon nitride charge. This theory is further confrmed by analyzing identical devices but with the silicon nitride cladding layer optimized to have intrinsic stresses of opposite sign and magnitude. The latter is achieved by a post annealing process which produces a defect healing and consequently a reduction of the silicon nitride charge. Raman measurements are also carried out to confrm the obtained results.Funding from projects TEC2016-76849-C2-2-R (MINECO/FEDER, UE) and NANOMET PLUS-Conselleria d'EducaciA3, Cultura i Esport - PROMETEOII/2014/034 is acknowledged. Irene Olivares also acknowledges the Universitat Politecnica de Valencia for funding his research staff training (FPI) grant. The authors would also like to thank Steven Van Roye from Ghent University for participating in the measurements of the annealed samples.Olivares-Sánchez-Mellado, I.; Ivanova-Angelova, T.; Sanchis Kilders, P. (2017). On the influence of interface charging dynamics and stressing conditions in strained silicon devices. Scientific Reports. 7(7241):1-8. https://doi.org/10.1038/s41598-017-05067-91877241Reed, G. T., Mashanovich, G., Gardes, F. Y. & Thomson, D. J. Silicon optical modulators. 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Phase-matched sum frequency generation in strained silicon waveguides using their second-order nonlinear optical susceptibility. Optics Express 19, 21707–21716 (2011).Schriever, C., Bohley, C., Schilling, J. & Wehrspohn, R. B. Strained Silicon Photonics. Materials 5, 889–908 (2012).Bianco, F. et al. Two-dimensional micro-Raman mapping of stress and strain distributions in strained silicon waveguides. Semiconductor Science and Technology 27, 085009 (2012).Chmielak, B. et al. Investigation of local strain distribution and linear electro-optic effect in strained silicon waveguides. Optics Express 21, 25324–25332 (2013).Aleali, A., Xu, D., Schmid, J. H., Cheben, P. & Winnie, N. Y. Optimization of stress-induced pockels effect in silicon waveguides for optical modulators. In Group IV Photonics (GFP), 2013 IEEE 10th International Conference on, 109–110 (IEEE, 2013).Puckett, M. W., Smalley, J. S., Abashin, M., Grieco, A. & Fainman, Y. Tensor of the second-order nonlinear susceptibility in asymmetrically strained silicon waveguides: analysis and experimental validation. Optics Letters 39, 1693–1696 (2014).Damas, P. et al. Wavelength dependence of pockels effect in strained silicon waveguides. Optics Express 22, 22095–22100 (2014).Khurgin, J. B., Stievater, T. H., Pruessner, M. W. & Rabinovich, W. S. On the origin of the second-order nonlinearity in strained Si-SiN structures. JOSA B 32, 2494–2499 (2015).Manganelli, C. L., Pintus, P. & Bonati, C. Modeling of strain-induced Pockels effect in Silicon. Optics Express 23, 28649–28666 (2015).Damas, P., Marris-Morini, D., Cassan, E. & Vivien, L. Bond orbital description of the strain-induced second-order optical susceptibility in silicon. Physical Review B 93, 165208 (2016).Cazzanelli, M. et al. Second-harmonic generation in silicon waveguides strained by silicon nitride. Nature Materials 11, 148–154 (2012).Schriever, C. et al. Second-Order Optical Nonlinearity in Silicon Waveguides: Inhomogeneous Stress and Interfaces. Advanced Optical Materials 3, 129–136 (2015).Borghi, M. B. et al. High-frequency electro-optic measurement of strained silicon racetrack resonators. Optics Letters 40, 5287–5290 (2015).Azadeh, S. S., Merget, F., Nezhad, M. & Witzens, J. On the measurement of the Pockels effect in strained silicon. Optics Letters 40, 1877–1880 (2015).Sharma, R. et al. Effect of dielectric claddings on the electro-optic behavior of silicon waveguides. Optics Letters 41, 1185–1188 (2016).Borghi, M. et al. Homodyne Detection of Free Carrier Induced Electro-Optic Modulation in Strained Silicon Resonators. Journal of Lightwave Technology 34, 5657–5668 (2016).Olivares, I., Ivanova, T., Pinilla-Cienfuegos, E. & Sanchis, P. A systematic optimization of design parameters in strained silicon waveguides to further enhance the linear electro-optic effect. 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Ultra-low loss hybrid ITO/Si thermo-optic phase shifter with optimized power consumption

© 2020 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] Typically, materials with large optical losses such as metals are used as microheaters for silicon based thermo-optic phase shifters. Consequently, the heater must be placed far from the waveguide, which could come at the expense of the phase shifter performance. Reducing the gap between the waveguide and the heater allows reducing the power consumption or increasing the switching speed. In this work, we propose an ultra-low loss microheater for thermo-optic tuning by using a CMOS-compatible transparent conducting oxide such as indium tin oxide (ITO) with the aim of drastically reducing the gap. Using finite element method simulations, ITO and Ti based heaters are compared for different cladding configurations and TE and TM polarizations. Furthermore, the proposed ITO based microheaters have also been fabricated using the optimum gap and cladding configuration. Experimental results show power consumption to achieve a pi phase shift of 10 mW and switching time of a few microseconds for a 50 mu m long ITO heater. The obtained results demonstrate the potential of using ITO as an ultra-low loss microheater for high performance silicon thermo-optic tuning and open an alternative way for enabling the large-scale integration of phase shifters required in emerging integrated photonic applications. (C) 2020 Optical Society of America under the terms of the OSA Open Access Publishing AgreementMinisterio de Economía y Competitividad (TEC2016-76849); Generalitat Valenciana (PROMETEO/2019/123); Ministerio de Ciencia, Innovación y Universidades (FPU17/04224).Parra Gómez, J.; Hurtado Montañés, J.; Griol Barres, A.; Sanchis Kilders, P. (2020). Ultra-low loss hybrid ITO/Si thermo-optic phase shifter with optimized power consumption. Optics Express. 28(7):9393-9404. https://doi.org/10.1364/OE.386959S93939404287Komma, J., Schwarz, C., Hofmann, G., Heinert, D., & Nawrodt, R. (2012). Thermo-optic coefficient of silicon at 1550 nm and cryogenic temperatures. Applied Physics Letters, 101(4), 041905. doi:10.1063/1.4738989Sun, J., Timurdogan, E., Yaacobi, A., Hosseini, E. S., & Watts, M. R. (2013). Large-scale nanophotonic phased array. Nature, 493(7431), 195-199. doi:10.1038/nature11727Shen, Y., Harris, N. C., Skirlo, S., Prabhu, M., Baehr-Jones, T., Hochberg, M., … Soljačić, M. (2017). Deep learning with coherent nanophotonic circuits. Nature Photonics, 11(7), 441-446. doi:10.1038/nphoton.2017.93Atabaki, A. H., Moazeni, S., Pavanello, F., Gevorgyan, H., Notaros, J., Alloatti, L., … Ram, R. J. (2018). Integrating photonics with silicon nanoelectronics for the next generation of systems on a chip. Nature, 556(7701), 349-354. doi:10.1038/s41586-018-0028-zPérez, D., Gasulla, I., Crudgington, L., Thomson, D. J., Khokhar, A. Z., Li, K., … Capmany, J. (2017). Multipurpose silicon photonics signal processor core. Nature Communications, 8(1). doi:10.1038/s41467-017-00714-1Sun, P., & Reano, R. M. (2010). Submilliwatt thermo-optic switches using free-standing silicon-on-insulator strip waveguides. Optics Express, 18(8), 8406. doi:10.1364/oe.18.008406Atabaki, A. H., Eftekhar, A. A., Yegnanarayanan, S., & Adibi, A. (2013). Sub-100-nanosecond thermal reconfiguration of silicon photonic devices. Optics Express, 21(13), 15706. doi:10.1364/oe.21.015706Masood, A., Pantouvaki, M., Goossens, D., Lepage, G., Verheyen, P., Van Campenhout, J., … Bogaerts, W. (2014). Fabrication and characterization of CMOS-compatible integrated tungsten heaters for thermo-optic tuning in silicon photonics devices. Optical Materials Express, 4(7), 1383. doi:10.1364/ome.4.001383Rosa, Á., Gutiérrez, A., Brimont, A., Griol, A., & Sanchis, P. (2016). High performace silicon 2x2 optical switch based on a thermo-optically tunable multimode interference coupler and efficient electrodes. Optics Express, 24(1), 191. doi:10.1364/oe.24.000191Jacques, M., Samani, A., El-Fiky, E., Patel, D., Xing, Z., & Plant, D. V. (2019). Optimization of thermo-optic phase-shifter design and mitigation of thermal crosstalk on the SOI platform. Optics Express, 27(8), 10456. doi:10.1364/oe.27.010456Wang, X., & Chiang, K. S. (2019). Polarization-insensitive mode-independent thermo-optic switch based on symmetric waveguide directional coupler. Optics Express, 27(24), 35385. doi:10.1364/oe.27.035385Atabaki, A. H., Shah Hosseini, E., Eftekhar, A. A., Yegnanarayanan, S., & Adibi, A. (2010). Optimization of metallic microheaters for high-speed reconfigurable silicon photonics. Optics Express, 18(17), 18312. doi:10.1364/oe.18.018312Yu, L., Yin, Y., Shi, Y., Dai, D., & He, S. (2016). Thermally tunable silicon photonic microdisk resonator with transparent graphene nanoheaters. Optica, 3(2), 159. doi:10.1364/optica.3.000159Schall, D., Mohsin, M., Sagade, A. A., Otto, M., Chmielak, B., Suckow, S., … Kurz, H. (2016). Infrared transparent graphene heater for silicon photonic integrated circuits. Optics Express, 24(8), 7871. doi:10.1364/oe.24.007871Yan, S., Zhu, X., Frandsen, L. H., Xiao, S., Mortensen, N. A., Dong, J., & Ding, Y. (2017). 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Ultra-compact non-volatile Mach-Zehnder switch enabled by a high-mobility transparent conducting oxide

[EN] Compact and broadband non-volatile silicon devices are mainly absorption based. Hence, access to low-loss non-volatile phase shifters is still a challenge. Here, this problem is addressed by using a high-mobility transparent conducting oxide such as cadmium oxide as a floating gate in a flash-like structure. This structure is integrated in a Mach¿Zehnder interferometer switch. Results show an active length of only 30 µm to achieve a ¿¿ phase shift. Furthermore, an extinction ratio of 20 dB and insertion loss as low as 1 dB may be attained. The device shows an optical broadband response and can be controlled with low-power pulses in the nanosecond range. These results open a new, to the best of our knowledge, way for enabling compact silicon-based phase shifters with non-volatile performance.Ministerio de Economia y Competitividad (TEC2016-76849); Generalitat Valenciana (PROMETEO/2019/123); Ministerio de Ciencia, Innovacion y Universidades (FPU17/04224).Parra Gómez, J.; Olivares-Sánchez-Mellado, I.; Ramos, F.; Sanchis Kilders, P. (2020). Ultra-compact non-volatile Mach-Zehnder switch enabled by a high-mobility transparent conducting oxide. Optics Letters. 45(6):1503-1506. https://doi.org/10.1364/OL.388363S1503150645

Impact of GST thickness on GST-loaded silicon waveguides for optimal optical switching

[EN] Phase-change integrated photonics has emerged as a new platform for developing photonic integrated circuits by integrating phase-change materials like GeSbTe (GST) onto the silicon photonics platform. The thickness of the GST patch that is usually placed on top of the waveguide is crucial for ensuring high optical performance. In this work, we investigate the impact of the GST thickness in terms of optical performance through numerical simulation and experiment. We show that higher-order modes can be excited in a GST-loaded silicon waveguide with relatively thin GST thicknesses (<100 nm), resulting in a dramatic reduction in the extinction ratio. Our results would be useful for designing high-performance GST/Si-based photonic devices such as non-volatile memories that could find utility in many emerging applications.This work is supported by grants PID2019-111460GB-I00, ICTS-2017-28-UPV-9F, and FPU17/04224 funded by MCIN/AEI/ 10.13039/501100011033, by "ERDF A way of making Europe" and "ESF Investing in your future". Funding from Generalitat Valenciana (PROMETEO/2019/123). Funding for open access charge: Universitat Politecnica de Valencia. The authors would like to thank Helen Urgelles for her help with the experimental measurements.Parra Gómez, J.; Navarro-Arenas, J.; Kovylina-Zabyako, M.; Sanchis Kilders, P. (2022). Impact of GST thickness on GST-loaded silicon waveguides for optimal optical switching. Scientific Reports. 12(1):1-9. https://doi.org/10.1038/s41598-022-13848-01912