A5030408538- Photonic and Optical Devices
- Advanced Fiber Laser Technologies
- Photonic Crystals and Applications
- Semiconductor Lasers and Optical Devices
- Advanced Fiber Optic Sensors
- Advanced Photonic Communication Systems
- Mechanical and Optical Resonators
- Optical Network Technologies
- Optical Coatings and Gratings
- Silicon Nanostructures and Photoluminescence
- Acoustic Wave Resonator Technologies
- Plasmonic and Surface Plasmon Research
- Neural Networks and Reservoir Computing
- Advanced MEMS and NEMS Technologies
- Ferroelectric and Piezoelectric Materials
- Photonic Crystal and Fiber Optics
- Nanowire Synthesis and Applications
- Radio Frequency Integrated Circuit Design
- Thin-Film Transistor Technologies
- Photorefractive and Nonlinear Optics
- Near-Field Optical Microscopy
- Microwave Engineering and Waveguides
- Semiconductor Quantum Structures and Devices
- Advanced Surface Polishing Techniques
- Essential Oils and Antimicrobial Activity
Indian Institute of Science Bangalore
2016-2025
Center for NanoScience
2016-2023
Centre de Nanosciences et de Nanotechnologies
2021
Ghent University
2007-2015
IMEC
2009-2014
KU Leuven
2013
Ghent University Hospital
2007-2012
University of Twente
2006
Abstract An overview is presented of the current state‐of‐the‐art in silicon nanophotonic ring resonators. Basic theory resonators discussed, and applied to peculiarities submicron photonic wire waveguides: small dimensions tight bend radii, sensitivity perturbations boundary conditions fabrication processes. Theory compared quantitative measurements. Finally, several more promising applications are discussed: filters optical delay lines, label‐free biosensors, active rings for efficient...
We give an overview of recent progress in passive spectral filters and demultiplexers based on silicon-on-insulator photonic wire waveguides: ring resonators, interferometers, arrayed waveguide gratings, echelle diffraction all benefit from the high-index contrast possible with silicon photonics.We show how current generation devices has improved crosstalk levels, insertion loss, uniformity due to fabrication process 193 nm lithography.
A new generation of Silicon-on-Insulator fiber-to-chip grating couplers which use a silicon overlay to enhance the directionality and thereby coupling efficiency is presented. Devices are realized on 200 mm wafer in CMOS pilot line. The fabricated fiber show -1.6 dB 3 bandwidth 80 nm.
We report subnanometer linewidth uniformity in silicon nanophotonics devices fabricated using high-volume CMOS fabrication tools. use wavelength-selective such as ring resonators, Mach-Zehnder interferometers, and arrayed waveguide gratings to assess the device nonuniformity within between chips. The were 193 or 248 nm optical lithography dry etching silicon-on-insulator wafer technology. Using lithography, we have achieved a of 2 (after lithography) 2.6 etch) over 200 mm wafer. Furthermore,...
PECVD silicon nitride photonic wire waveguides have been fabricated in a CMOS pilot line. Both clad and unclad single mode were measured at λ = 532, 780, 900 nm, respectively. The dependence of loss on width, wavelength, cladding is discussed detail. Cladded multimode singlemode show well below 1 dB/cm the 532-900 nm wavelength range. For waveguides, losses achieved whereas range 1-3 for 780 532
High-index contrast silicon-on-insulator technology enables wavelength-scale compact photonic circuits. We report fabrication of circuits in using complementary metal-oxide-semiconductor processing technology. By switching from advanced optical lithography at 248 to 193 nm, combined with improved dry etching, a substantial improvement process window, linearity, and proximity effect is achieved. With the developed process, propagation bending loss wires were characterized. Measurements...
The current trend in silicon photonics towards higher levels of integration as well the model using CMOS foundries for fabrication are leading to a need standardization substrate parameters and processes. In particular, several established research development that grant general access, silicon-on-insulator wafers with thickness 220 nm have become standard which devices circuits be designed. this study we investigate role device layer design optimization various components integrated typical...
We report a low-loss, hybrid silicon waveguide geometry that consists of straight rib sections with propagation loss 0.27 ± 0.012 dB/cm and compact photonic wire bends. The waveguides are both single mode connected through short double-etched linear taper section. To reduce bend losses, circular bends were combined variable adiabatic seminatural spline shapes only limited footprint penalty.
We propose hydrogenated amorphous silicon nanowires as a platform for nonlinear optics in the telecommunication wavelength range. Extraction of parameter these photonic reveals figure merit larger than 2. It is observed that optical properties waveguides degrade with time, but this degradation can be reversed by annealing samples. A four wave mixing conversion efficiency + 12 dB demonstrated 320 Gbit/s serial waveform data sampling experiment 4 mm long nanowire.
In this paper, we review our work on efficient interfaces between a silicon-on-insulator photonic IC and single-mode optical fiber based grating structures. Several device configurations are presented that provide high efficiency, polarization insensitive, broadband coupling small footprint. The alignment tolerance the fact interface is out-of-plane opportunities for easy packaging wafer-scale testing of IC. Finally, an probe structure defined facet described.
<para xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> We present measurement results of an ultracompact four-channel silicon-on-insulator planar concave grating demultiplexer fabricated in a complimentary metal–oxide–semiconductor line using deep-ultraviolet lithography. The has four output channels separated by 20 nm and footprint only 280 <emphasis><formula formulatype="inline"><tex>$\mu$</tex></formula></emphasis>m<emphasis><formula...
Advanced modulation formats call for suitable IQ modulators.Using the silicon-on-insulator (SOI) platform we exploit linear electrooptic effect by functionalizing a photonic integrated circuit with an organic χ (2) -nonlinear cladding.We demonstrate that this silicon-organic hybrid (SOH) technology allows fabrication of modulators generating 16QAM signals data rates up to 112 Gbit/s.To best our knowledge, is highest single-polarization rate achieved so far silicon-integrated modulator.We...
We present what we believe to be the first study of parametric amplification in hydrogenated amorphous silicon waveguides. Broadband on/off up 26.5 dB at telecom wavelength is reported. Measured nonlinear parameter 770 W(-) m(-1), absorption 28 W(-1) bandgap 1.61 eV.
Using an advanced 300mm CMOS-platform, we report record-low and highly-uniform propagation loss: 0.45±0.12dB/cm for wires, 2dB/cm slot waveguides. For WDM devices, demonstrate channel variation(3-σ) within-wafer within-device of 6.1nm 1.2nm respectively.
We review recent progress in nanophotonic devices for compact optical interconnect networks. focus on microdisk-laser-based transmitters and discuss improved design advanced functionality including all-optical wavelength conversion flip-flops. Next we the fabrication uniformity of passive routing circuits their thermal tuning. Finally, performance a selective detector.
we report on a highly efficient grating coupler between an optical fiber and silicon photonic circuit. Using layers of Si/SiO2 as Bragg mirror amorphous Si have measured coupling efficiency 69.5%.
In this paper, the use of diffractive grating structures to efficiently interface between a single mode fiber and high index contrast waveguide circuit is outlined.We show that allow for broadband efficiency coupling.Since no polished facet required on photonic integrated with optical fiber, fiber-to-chip couplers enable wafer-scale testing, reducing cost testing large scale circuits.We two-dimensional can solve problem huge polarization dependence circuits.Finally, an probe presented, which...
We demonstrate a polarization rotator fabricated using 4 etch-step complementary metal-oxide-semiconductor (CMOS)-compatible process including layer depositions on silicon-on-insulator wafer. The measured rotation efficiency is over wavelength range of 80 nm. A robustness investigation shows that the design compatible with CMOS fabrication capabilities.
Fiber to chip coupling is a critical aspect of any integrated photonic circuit. In terms ease fabrication as well wafer-scale testability, surface grating couplers are by far the most preferred scheme circuits. past decade, considerable effort has been made for designing efficient on Silicon-on-Insulator (SOI) and other allied platforms. Highly with sub-dB performance have now demonstrated. this article, we review recent advances develop coupler designs variety applications SOI platform. We...
Silicon nitride is a promising high-index material for dense photonic circuits and applications in the visible-midinfrared wavelength regime. Design, fabrication, optical characterization of silicon waveguides at visible-near-infrared are presented. Finally, design experimental results presented first time linear focused grating couplers (GCs) near-infrared (900 nm) plasma-enhanced chemical vapor deposition wires (220 × 500 compared with theoretical simulations. An efficiency 5.7 6.5 dB 1-dB...
We report supercontinuum (SC) generation centered on the telecommunication C-band (1550 nm) in CMOS compatible hydrogenated amorphous silicon waveguides.A broadening of more than 550nm is obtained 1cm long waveguides different widths using as pump picosecond pulses with chip peak power low 4W.
We demonstrate static and dynamic bulk refractive index measurement using slot-waveguide based ring resonator. A detailed simulation is performed to optimize the geometry for maximum sensitivity. The on-chip measurements are a slot waveguide resonator by applying aqueous solutions of acids bases at different concentrations. Based on these measurements, we derive relation change per unit in concentration liquids water. experimentally measured sensitivity 476 nm/RIU, enabling limit detection...
Abstract Silicon Nitride ( SiN ) is emerging as a promising material for variety of integrated photonic applications. Given its low index contrast however, key challenge remains to design efficient couplers the numerous platforms in photonics portfolio. Using combination bottom reflector and chirp generating algorithm, we propose demonstrate high efficiency, grating on two distinct platforms. For partially etched 500 nm thick , calculated peak efficiency −0.5 dB/coupler predicted, while...