A5081444016- Photonic and Optical Devices
- Advanced Fiber Laser Technologies
- Optical Network Technologies
- Mechanical and Optical Resonators
- Photonic Crystals and Applications
- Advanced Photonic Communication Systems
- Advanced Fiber Optic Sensors
- Neural Networks and Reservoir Computing
- Semiconductor Lasers and Optical Devices
- Magneto-Optical Properties and Applications
- Optical Coatings and Gratings
- Dental materials and restorations
- Gyrotron and Vacuum Electronics Research
- Silicon Nanostructures and Photoluminescence
- Advanced optical system design
- Advanced Optical Imaging Technologies
Praevium Research (United States)
2025
King Abdullah University of Science and Technology
2024
Universidade Estadual de Campinas (UNICAMP)
2013-2022
University of California, San Diego
2016-2017
The integration of miniaturized optical spectrometers into mobile platforms will have an unprecedented impact on applications ranging from unmanned aerial vehicles (UAVs) to phones. To address this demand, silicon photonics stands out as a platform capable delivering compact and cost-effective devices. Fourier transform spectrometer (FTS) is largely used in free-space spectroscopy, its implementation contribute bringing broadband operation fine resolution the chip scale. integrated FTS...
Single microring resonators have been used in applications such as wavelength multicasting and microwave photonics, but the dependence of free spectral range with ring radius imposes a trade-off between required GHz optical channel spacing, footprint power consumption. We demonstrate four-channel all-optical using only 1 mW control power, converted spacing 40-60 GHz. Our device is based on compact embedded design fabricated scalable SOI platform. The coexistence close resonance high finesse...
Optical mode-splitting is an efficient tool to shape and fine-tune the spectral response of resonant nanophotonic devices. The active control mode-splitting, however, either small or accompanied by undesired resonance-shifts, often much larger than resonance splitting. We report a mechanism that enables reconfigurable widely tunable mode splitting while efficiently mitigating shifts. This achieved actively controlling excitation counter-traveling modes in coupled resonators. transition from...
We experimentally investigate the application of magnetic fluids (MFs) on integrated silicon photonics. Using a ferrofluid-clad microring resonator, we demonstrate active control resonances by applying an external field. Relatively high loaded quality factors order 6000 are achieved, despite optical losses introduced nanoparticles. resonance shifts 185 pm in response to 110 Oe strong field, corresponding overall refractive index change -3.2×10-3 for cladding MF. The combination MFs and...
Coupled resonators are commonly used to achieve tailored spectral responses and allow novel functionalities in a broad range of applications. The Temporal Coupled-Mode Theory (TCMT) provides simple general tool that is widely model these devices. Relying on TCMT coupled might however be misleading some circumstances due the lumped-element nature model. In this article, we report an important limitation related prediction dark states. Studying system composed three microring resonators,...
Hybrid refractive-diffractive lenses combine the light efficiency of refractive with information encoding power diffractive optical elements (DOE), showing great potential as next generation imaging systems. However, accurately simulating such hybrid designs is generally difficult, and in particular, there are no existing differentiable image formation models for sufficient accuracy.In this work, we propose a new ray-tracing wave-propagation (ray-wave) model accurate simulation both...
We propose and demonstrate a method to compensate insertion losses in Si photonics devices based on ring resonators fabricated SOI foundries, with no additional chip area used. It consists the employment of Er:Al <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sub> O xmlns:xlink="http://www.w3.org/1999/xlink">3</sub> as upper cladding layer standard Si/SiO rings, requiring only one simple post-processing step. The is modeled detail,...
We demonstrate an integrated photonic platform comprising a refractive index (RI) sensor based on Photonic Molecule (PM) that effectively mitigates the influence of environmental perturbations using differential measurement scheme while providing high quality-factor (Q) resonances. The RI consists partially unclad microdisk resonator coupled to external clad microring fabricated silicon-on-insulator (SOI) platform. report sensitivity 24 nm/RIU, achieving limit detection (LOD) 1.7 × 10 <sup...
Research thrusts in silicon photonics are developing control operations using higher order waveguide modes for next generation high-bandwidth communication systems. In this context, devices allowing optical processing of multiple can reduce architecture complexity and enable flexible on-chip networks. We propose demonstrate a hybrid resonator dually resonant at the 1st 2nd waveguide. observe 8 dB extinction ratio modal conversion range 20 nm quasi-TE mode input.
Optical sensors based on integrated photonics have experienced impressive advancements in the past few decades and represent one of main sensing solutions many areas including environmental medical diagnostics. In this context, optical microcavities are extensively employed as refractive index (RI) sensors, providing sharp resonances that allow detection very small variations surrounding RI. With increased sensitivity, however, device is subjected to perturbations can also change RI, such...
We describe the fabrication optimization of Er-doped Al2O3 films for III-V integrated photonics. Smooth and thick films, with high refractive index Erbium emission in C-band spectrum (1530 nm to 1565 nm) are obtained using co-sputtering technique. Thermal annealing at 850 °C is shown provide highest Photoluminescence intensity films. However, onset crystallization leads large fluctuation index. also show that temperatures larger than 600 causes well intermixing laser structure. Therefore,...
We demonstrate the generation and control of optical resonance mode-splitting arising from a single-notch using coupled silicon microring resonators with electrically controlled counter-propagating mode excitation.
In this work we present analytical and experimental results indicating that Coupled Mode Theory, unlike the Transfer Matrix Method, may have limitations in predicting behavior of photonic molecules based on embedded coupled microring cavities. We show resonant mode-based approach fails to provide correct transmission spectrum for some important cavity configurations, although correctly existence these modes as eigenstates system. The measured a CMOS compatible tunable molecule is used...
We describe the integration of erbium-doped Al <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sub> O xmlns:xlink="http://www.w3.org/1999/xlink">3</sub> material with InGaAs/GaAs quantum well lasers emitting at 980 nm, demonstrating possibility integrating III-V based pumping and materials suitable for optical amplification planar photonics. Combining Er-doped compounds is challenging since ion activation usually requires high temperature...
We demonstrate how CMOS compatible photonic molecules (PM) can break the fundamental interdependence among quality factor (Q), channel spacing and size of microring resonators. Different PM architectures are presented for efficient compact optical signal processing.
We demonstrate a multimode device simultaneously resonant at the 1st and 2nd order modes of adjacent silicon waveguides. This introduces design flexibility represents an interesting alternative to traditional mode conversion devices.
We experimentally investigate a ferrofluid-clad silicon microring resonator-based magnetic field sensor. The device presents relatively high loaded quality factors (~ 6,000) and resonance shifts of 185 pm in response to 110 Oe strong field.
We report on our observation of thermal control transmission spectra a micro-ring resonator coupled to low finesse etalon. Thermal tuning the device changes coupling strength and losses between etalon ring resulting in wide variety line shapes ranging from symmetric asymmetric Fano-like electromagnetically induced transparency (EIT)-like behavior. The capability modify spectral by thermally two resonators has obvious applications optical communication networks relevance sensor where it may...
Get PDF Email Share with Facebook Tweet This Post on reddit LinkedIn Add to CiteULike Mendeley BibSonomy Citation Copy Text G. F. M. de Rezende, C. Souza, L. A. Barea, Moras, P. Jarschel, Roelkens, and N. Frateschi, "Tunable, Reconfigurable Active Silicon Photonic Devices employing Molecules," in Latin America Optics Photonics Conference, OSA Technical Digest (Optica Publishing Group, 2018), paper Th2A.3. Export BibTex Endnote (RIS) HTML Plain alert Save article
In this work, we demonstrate an integrated platform comprising a refractive index (RI) sensor based on Photonic Molecule (PM) that effectively mitigates the influence of environmental perturbations using differential measurement scheme while providing high quality-factor (Q) resonances. The RI consists exposed microdisk resonator coupled to external clad microring fabricated silicon-on-insulator (SOI) platform. We report sensitivity 23 nm/RIU, achieving limit detection (LOD) 1.6 x 10-3 units...
We demonstrate four-channel all-optical wavelength multicasting using only 1 mW of pump power and channel spacing 40-60 GHz. Our device is based on a compact embedded microring design fabricated scalable SOI platform.