41 research outputs found
Demonstration of an integrated LiNbO3 Synchronized Double Phase Modulator and its Applications to Dual-Pump Fiber Optical Parametric Amplifiers and Wavelength Converters
International audienceWe report the fabrication of an integrated LiNbO3 Y-junction synchronized double phase modulator fully packaged for RF-application up to 40 GHz. This optical modulator allows for delivering simultaneously counter-phase high-speed modulation and coupling for two input channels. It was designed for application to fiber-optical parametric amplifier and wavelength converters for suppressing idler spectral broadening and signal gain distortion caused by phase modulation itself. With this component, Idler spectral broadening suppression is experimentally demonstrated over all the parametric gain band of a twopump parametric amplifier operating in the 1.55 ”m region. In addition, we present a useful technique for straightforward and full coupling of the pumps and the signal
Technology Contribution to Improve Autistic Children Life Quality
To review published literature on the use of technology and how it has improved autistic children life style. A systematic review of the English literature was performed using the PRISMA guideline. Papers indexed in WOS and Scopus databases were included, adjusted to a timeline between 2016 and 2020 and focused on mobile technology, interventions, improvement of social behavior and communication and autism, aimed to describe the most used mechanism to improve autistic life style. Thirty two (32) papers were included in the review. We obtained 14 papers on the Scopus database and 18 on the WOS database. The majority of studies evidenced the use of virtual reality, mobile devices, video modelling and robots as the most common applications for autism therapies. Technology has caused an improvement in autistic children life quality. The development of mobile applications, virtual reality applications and robots have showed a positive impact reflected in the performance of daily activities and a better understanding of how they feel, how to behave, how to express themselves and interact with others. Technology gives the opportunity to monitor children status; and offers adaptability, safety, and accuracy of the information
2023 Astrophotonics Roadmap: pathways to realizing multi-functional integrated astrophotonic instruments
This is the final version. Available on open access from IOP Publishing via the DOI in this recordData availability statement:
The data that support the findings of this study are available upon reasonable request from the authors.Photonic technologies offer numerous functionalities that can be used to realize astrophotonic instruments. The most spectacular example to date is the ESO Gravity instrument at the Very Large Telescope in Chile that combines the light-gathering power of four 8 m telescopes through a complex photonic interferometer. Fully integrated astrophotonic devices stand to offer critical advantages for instrument development, including extreme miniaturization when operating at the diffraction-limit, as well as integration, superior thermal and mechanical stabilization owing to the small footprint, and high replicability offering significant cost savings. Numerous astrophotonic technologies have been developed to address shortcomings of conventional instruments to date, including for example the development of photonic lanterns to convert from multimode inputs to single mode outputs, complex aperiodic fiber Bragg gratings to filter OH emission from the atmosphere, complex beam combiners to enable long baseline interferometry with for example, ESO Gravity, and laser frequency combs for high precision spectral calibration of spectrometers. Despite these successes, the facility implementation of photonic solutions in astronomical instrumentation is currently limited because of (1) low throughputs from coupling to fibers, coupling fibers to chips, propagation and bend losses, device losses, etc, (2) difficulties with scaling to large channel count devices needed for large bandwidths and high resolutions, and (3) efficient integration of photonics with detectors, to name a few. In this roadmap, we identify 24 key areas that need further development. We outline the challenges and advances needed across those areas covering design tools, simulation capabilities, fabrication processes, the need for entirely new components, integration and hybridization and the characterization of devices. To realize these advances the astrophotonics community will have to work cooperatively with industrial partners who have more advanced manufacturing capabilities. With the advances described herein, multi-functional integrated instruments will be realized leading to novel observing capabilities for both ground and space based platforms, enabling new scientific studies and discoveries.National Science Foundation (NSF)NAS
Hybrid CAD modelling dedicated to the design of a QPSK modulator on LiNbO3"
International audienceThis paper describes a co-modelling approach based on electromagnetic and electro-optic simulations. Such approach is applied to the design of a Mach-Zehnder intensity modulator (MZI) at four lanes integrated on Z-cut lithium niobate, applied to a QPSK modulation. As we will see, our original procedure contributes to the optimization of QPSK modulator behaviour. The theoretical and experimental results are encouraging
Modelling and optimization of low chirp MachâZehnder modulators with ferroâelectric domain inverted section
Modeling and optimization of low chirp LiNbO3 Mach-Zehnder modulators with an inverted ferroelectric domain section
Domain inversion under coplanar waveguide electrodes is proposed to improve the frequency-chirping behavior of Z-cut LiNbO3 MachâZehnder modulators. This is achieved by introducing a phase reversal electrode section in tandem with inverted ferroelectric domains. The method opens the way to broad-band single-drive modulators with predetermined chirp parameter. The experimental results obtained at 10 Gb/s confirm the possibility of lowering the chirp parameter of a Z-cut modulator, while keeping a halfwave voltage lower than 5 V
A LiNbO3 Active Switch Coupler at 2050 nm for Differential Absorption Lidar and Atmospheric Gas Monitoring
International audienceWe report, for what we believe is the first time, the design and the fabrication of an active optical switch working at 2050 nm. The switch uses a lithium niobate crystal and is fully packaged. It is based on a three-section alternating Delta beta configuration. It is dedicated to differential absorption lidar (DIAL) and atmospheric gas monitoring
Extended analytical formulation based on Marcatili's approach coupled to effective index method for pedestal waveguides: convergence with numerical methods
International audienc