Explanipedia

Integrated silicon nitride devices via inverse design Open

Julián L. Pita, Narges Dalvand, Michaël Ménard · 2025

Integrated Silicon Nitride Devices via Inverse Design Open

Julián L. Pita, Narges Dalvand, Michaël Ménard · 2025

Integrated photonic devices made of silicon nitride (SiN), which can be integrated with silicon-on-insulator and III-V platforms, are expected to drive the expansion of silicon photonics technology. However, the relatively low refractive i…

Reconfigurable electrostatically actuated 1 × 5 rotary MOEMS switch Open

Navid Heidari, Julián L. Pita, Seyedfakhreddin Nabavi, Michaël Ménard, Frédéric Nabki · 2025

Optical switches play a critical role in optical communication systems, meeting the growing demand for high-speed data transfer. Among optical switches, micro-opto-electro-mechanical system (MOEMS) switches stand out for their reconfigurab…

Effect of Beam-Steering Angle, Operation Wavelength and Mean Inter-Element Distance on the Side-Lobe Levels of Integrated Optical Phased Arrays under Beam-Steering Operation Open

Ivan Aldaya, Bruna Dias Pires de Souza, Rafael A. Penchel, Julián L. Pita, Mirian P. dos Santos , et al. · 2023

Integrated optical phased arrays (OPAs) play an important role in a broad range of applications. Fabrication constraints, however, pose a limit to the minimum inter-element separation that further results in high-intensity side lobes. The …

Silicon nitride TM-pass polarizer using inverse design Open

Julián L. Pita, Frédéric Nabki, Michaël Ménard · 2023

Integrated silicon nitride polarizers play a critical role in the design of complex integrated devices such as filters, switches, and large Mach-Zehnder interferometer networks. These devices require precise control of both polarizations o…

Design of a silicon Mach–Zehnder modulator via deep learning and evolutionary algorithms Open

Romulo Aparecido de Paula, Ivan Aldaya, Tiago Sutili, Rafael Figueirêdo, Julián L. Pita , et al. · 2023

As an essential block in optical communication systems, silicon (Si) Mach–Zehnder modulators (MZMs) are approaching the limits of possible performance for high-speed applications. However, due to a large number of design parameters and the…

Two-axis MEMS positioner for waveguide alignment in silicon nitride photonic integrated circuits Open

Almur A. S. Rabih, Suraj Sharma, Julián L. Pita, Michaël Ménard, Frédéric Nabki · 2023

Alignment is critical for efficient integration of photonic integrated circuits (PICs), and microelectromechanical systems (MEMS) actuators have shown potential to tackle this issue. In this work, we report MEMS positioning actuators desig…

Design of a Silicon Mach-Zehnder Modulator via Deep Learning and Evolutionary Algorithms Open

Romulo Aparecido de Paula, Ivan Aldaya, Tiago Sutili, Rafael Figueirêdo, Julián L. Pita , et al. · 2023

As an essential block in optical communication systems, silicon (Si) Mach-Zehnder modulators (MZMs) are approaching the limits of possible performance for high-speed applications. However, due to a large number of design parameters and the…

Impairment mitigation in dual-polarization single-span optical digital coherent systems using support vector classifiers Open

Ivan Aldaya, Lúcio Borges, Camila Carlino da Costa, Julián L. Pita, Rafael A. Penchel , et al. · 2023

We report on using support vector classifiers (SVCs) to mitigate the residual and fiber-induced nonlinear distortions in a digital coherent optical communication system employing dual-polarization 16-ary quadrature amplitude modulation wit…

Compact dual-polarization silicon integrated couplers for multicore fibers Open

Julián L. Pita, Lucas G. Rocha, Jun Yang, Şükrü Ekin Kocabaş, Ming-Jun Li , et al. · 2022

Made available in DSpace on 2022-04-28T17:20:28Z (GMT). No. of bitstreams: 0\n Previous issue date: 2021-08-01

Compensation of crosstalk in optical spatial division multiplexing systems employing multiple-input and multiple-output processing Open

Débora Beatriz Claro Zanitti, Cintya W. O. Benedito, Rafael A. Penchel, Julián L. Pita, Marcelo L. F. Abbade , et al. · 2022

The development of digital coherent optical communication technology has boosted the system capacity close to the nonlinear Shannon limit imposed by the combination of additive noise and nonlinear distortion.In this context, spatial divisi…

Self-Phase Modulation and Inter-Polarization Cross-Phase Modulation Mitigation in Single-Channel Dp-16qam Coherent Pon Employing 4d Clustering Open

Camila Pinto da Costa, Lúcio Borges, Rafael A. Penchel, Marcelo L. F. Abbade, Elias Giacoumidis , et al. · 2022

Efficient integrated tri-modal coupler for few-mode fibers Open

Julián L. Pita, Lucas G. Rocha, Jun Yang, Şükrü Ekin Kocabaş, Ming-Jun Li , et al. · 2022

Agradecimentos: Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (88881.311020/2018); Fundação de Amparo à Pesquisa do Estado de São Paulo (2015/24517-8, 2016/19270-6, 2018/25339-4); Conselho Nacional de Desenvolvimento Científi…

Compact dual-polarization silicon integrated couplers for multicore fibers Open

Julián L. Pita, Lucas G. Rocha, Jun Yang, Şükrü Ekin Kocabaş, Ming-Jun Li , et al. · 2021

Compact fiber-to-chip couplers play an important role in optical interconnections, especially in data centers. However, the development of couplers has been mostly limited to standard single-mode fibers, with few devices compatible with mu…

Design of Compact Arbitrary-Ratio Multimode Power Splitters Based on Topological Derivative Open

Julián L. Pita, Ivan Aldaya, Paulo Dainese, Lucas H. Gabrielli · 2020

Made available in DSpace on 2021-06-25T11:44:49Z (GMT). No. of bitstreams: 0\n Previous issue date: 2020-09-15

Optimization of Element Positions in Linear Optical Phased Arrays for Broad Beam Steering Operation Open

B.A. de Souza, Ivan Aldaya, Julián L. Pita, Marcelo L. F. Abbade, Paulo F. Jarschel , et al. · 2020

Fiber-induced nonlinear limitation in 400-Gbps single-channel coherent optical interconnects Open

Ivan Aldaya, Rômulo Paula, Bruna Dias Pires de Souza, Lucas Marim, Lúcio Borges , et al. · 2020

Histogram Based Clustering for Nonlinear Compensation in Long Reach Coherent Passive Optical Networks Open

Ivan Aldaya, Elias Giacoumidis, Geraldo de Oliveira, Jinlong Wei, Julián L. Pita , et al. · 2019

In order to meet the increasing capacity requirements, network operators are extending their optical infrastructure closer to the end-user while making more efficient use of the resources. In this context, long reach passive optical networ…

Optimization of the electromagnetic scattering problem based on the topological derivative method Open

Julián L. Pita, Alan A. S. Amad, Lucas H. Gabrielli, Antônio André Novotny · 2019

A new optimization method based on the topological derivative concept is developed for the electromagnetic design problem. Essentially, the purpose of the topological derivative method is to measure the sensitivity of a given shape functio…

Generation and recombination of free carriers in silicon nano-waveguides Open

Paulo Dainese, Ivan Aldaya, Andrés Gil-Molina, Lucas H. Gabrielli, H.L. Fragnito , et al. · 2019

Generation and recombination of free carriers in silicon photonics is fundamental to understand several nonlinear optical phenomena and engineer novel devices. Particularly in strip nano-waveguides, the tightly confined optical field resul…

Characterization of surface-states in a hollow core photonic crystal fiber Open

Erick Lamilla, Maicon S. Faria, Ivan Aldaya, Paulo F. Jarschel, Julián L. Pita , et al. · 2018

Surface or edge states represent an important class of modes in various photonic crystal systems such as in dielectric topological insulators and in photonic crystal fibers. In the later, strong attenuation peaks in the transmission spectr…

Optical free-carrier generation in silicon nano-waveguides at 1550 nm Open

Andrés Gil-Molina, Ivan Aldaya, Julián L. Pita, Lucas H. Gabrielli, H.L. Fragnito , et al. · 2018

We report on time-resolved pump and probe characterization of linear and nonlinear optical generation of free carriers in a silicon strip nano-waveguide at the 1550 nm communication band. Analytical expressions were developed to extract th…

A Wideband Diplexer for Ka-Band Passive Intermodulation Measurement Open

Davide Smacchia, Carlos Carceller, M. Guglielmi, Pablo Soto, Vicente E. Boria , et al. · 2018

In this paper we propose a novel Ka-band waveguide diplexer for passive intermodulation (PIM) measurements. Due to the higher operating frequency, this type of measurement setup usually requires wideband filters. In addition, due to the ve…

Design of a compact CMOS-compatible photonic antenna by topological optimization Open

Julián L. Pita, Ivan Aldaya, Paulo Dainese, Hugo E. Hernández‐Figueroa, Lucas H. Gabrielli · 2018

Photonic antennas are critical in applications such as spectroscopy, photovoltaics, optical communications, holography, and sensors. In most of those applications, metallic antennas have been employed due to their reduced sizes. Neverthele…

Recovery of highly-dispersive modes using a wavelength-resolved modified S2 imaging method Open

Erick Lamilla, Ivan Aldaya, Maicon S. Faria, Paulo F. Jarschel, Julián L. Pita , et al. · 2018

We present a modified w avelength-resolved S 2 m ethod t hat a llows r ecovery of highly-dispersive modes. We employed this method using a variable window spectrogram to characterize a hollow core photonic crystal fiber where several surfa…

Characterization of linear and nonlinear carrier generation in silicon nano-waveguides at 1550 nm Open

Andrés Gil-Molina, Ivan Aldaya, Julián L. Pita, Lucas H. Gabrielli, H.L. Fragnito , et al. · 2018

We characterize the generation of free-carriers in a silicon strip nano-waveguide at 1550 nm performing pump-and-probe measurements. Compared with bulk silicon, we identified a higher effective two-photon absorption coefficient and a signi…

Side-lobe Level Reduction in Two-dimensional Optical Phased Array Antennas Open

Julián L. Pita, Ivan Aldaya, Octávio J. S. Santana, Luís E. E. de Araújo, Paulo Dainese , et al. · 2018

We experimentally demonstrate that by arranging the array elements according to Fermat's spiral, the side lobe level of an 8-element SOI-array is reduced by 0:9 dB. Additional experiments show a 6:9 dB reduction for 64-elements.

Side-lobe level reduction in bio-inspired optical phased-array antennas Open

Julián L. Pita, Ivan Aldaya, Octávio J. S. Santana, Luís E. E. de Araújo, Paulo Dainese , et al. · 2017

Phased arrays are expected to play a critical role in visible and infrared wireless systems. Their improved performance compared to single element antennas finds uses in communications, imaging, and sensing. However, fabrication of photoni…

Nonlinear carrier dynamics in silicon nano-waveguides Open

Ivan Aldaya, Andrés Gil-Molina, Julián L. Pita, Lucas H. Gabrielli, H.L. Fragnito , et al. · 2017

The understanding of free-carrier dynamics in silicon photonic nano-waveguides and micro-cavities is fundamental to several nonlinear optical phenomena. Through time-resolved pump and probe experiments, a complex and nonlinear carrier reco…

Nonlinear carrier dynamics in silicon nanowaveguides Open

Ivan Aldaya, Andrés Gil-Molina, Julián L. Pita, Lucas H. Gabrielli, H.L. Fragnito , et al. · 2017

Carrier recombination dynamics in strip silicon nano-waveguides is analyzed through time-resolved pump-and-probe experiments, revealing a complex recombination dynamics at densities ranging from 10^14 to 10^17 cm^-3. Our results show that …

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