We report on the experimental demonstration and analysis of a new waveguide principle using subwavelength gratings. Unlike other periodic waveguides such as line-defects in 2D photonic crystal lattice, grating confines light conventional index-guided structure does not exhibit optically resonant behaviour. Subwavelength silicon-on-insulator are fabricated with single etch step allow for flexible control effective refractive index core simply by lithographic patterning. Experimental...

We use subwavelength gratings (SWGs) to engineer the refractive index in microphotonic waveguides, including practical components such as input couplers and multiplexer circuits. This technique allows for direct control of mode confinement by changing a waveguide core over range broad 1.6-3.5 lithographic patterning. demonstrate two experimental examples engineering, namely, fiber-chip coupler with coupling loss small -0.9dB minimal wavelength dependence planar SWG nanostructure, which acts...

Segmenting silicon waveguides at the subwavelength scale produce an equivalent homogenous material. The geometry of waveguide segments provides precise control over modal confinement, effective index, dispersion and birefringence, thereby opening up new approaches to design devices with unprecedented performance. Indeed, ever-improving lithographic technologies offering sub-100-nm patterning resolution in photonics platform, many practical based on structures have been demonstrated recent...

Abstract Nanophotonic beamsplitters are fundamental building blocks in integrated optics, with applications ranging from high speed telecom receivers to biological sensors and quantum splitters. While high‐performance multiport have been demonstrated several material platforms using multimode interference couplers, their operation bandwidth remains fundamentally limited. Here, we leverage the inherent anisotropy dispersion of a sub‐wavelength structured photonic metamaterial demonstrate...

We demonstrate a 50-channel high-resolution arrayed waveguide grating microspectrometer with 0.2 nm channel spacing on silicon-on-insulator (SOI) platform. The chip size is 8 mm x mm. High density and spectral resolution are achieved using high aspect ratio 0.6 mum 1.5 apertures to inject the light into input combiner intercept different channels at output focal region. measured crosstalk <-10 dB, 3 dB bandwidth 0.15 nm, insertion loss -17 near central wavelength of lambda = 1.545 mum.

We demonstrate a new, highly sensitive evanescent field sensor using silicon-on-insulator (SOI) photonic wire waveguides. Theoretical analysis shows that thin SOI waveguides can provide higher sensitivity over devices based in all other common planar waveguide material systems for the probing of both adsorbed biomolecular layers and bulk homogeneous solutions. A Si was incorporated into Mach-Zehnder interferometer sensor, configured to monitor index change solution. High effective 0.31 per...

We propose a new method for mode conversion and coupling between an optical fiber sub-micrometer waveguide using subwavelength grating (SWG) with period less than the 1st order Bragg period. The coupler principle is based on gradual modification of effective index by SWG effect that at same time frustrates diffraction minimizes reflection loss. demonstrate proposed two-dimensional Finite Difference Time Domain (FDTD) calculations various structures designed silicon-on-insulator (SOI)...

We report on the design, simulation and experimental demonstration of a new type waveguide crossing based subwavelength gratings in silicon waveguides.We used 3D finite-difference time-domain simulations to minimize loss, crosstalk polarization dependence.Measurement fabricated devices show that our crossings have loss as low -0.023 dB/crossing, dependent < 0.02 dB <-40 dB.

We demonstrate folded waveguide ring resonators for biomolecular sensing. show that extending the cavity length increases resonator quality factor, and thereby enhances sensor resolution minimum level of detection, while at same time relaxing tolerance on coupling conditions to provide stable large resonance contrast. The spiral path geometry allows a 1.2 mm long be enclosed in 150 microm diameter area. is used monitor streptavidin protein binding with detection limit approximately 3...

We propose a silicon waveguide-fiber grating coupler that uses subwavelength microstructure to achieve continuously variable strength yet can be fabricated using only single etch step. By adjusting the at every point along grating, optimized give high field overlap with optical fiber mode and also minimize backreflections incident waveguide path. Our design example is for quasi-TM in photonic-wire waveguide, as required evanescent-field-sensing applications. A of up 94% standard single-mode...

We demonstrate a silicon photonic wire waveguide biosensor array chip for the simultaneous monitoring of different molecular binding reactions. The is compatible with automated commercial spotting tools and contains monolithically integrated microfluidic channel sample delivery. Each sensor element 1.8-mm-long spiral folded within 130 microm diameter spot incorporated in balanced Mach-Zehnder interferometer near temperature independent response. sensors are arranged 400 spacing grid pattern...

We demonstrate efficient, low power, continuous-wave four-wave mixing in the C-band, using a high index doped silica glass micro ring resonator having Q-factor of 1.2 million. A record conversion efficiency for this kind device is achieved over bandwidth 20nm. show theoretically that characteristic dispersion enables phase-matching > 160nm.

We propose an ultra-broadband multimode interference (MMI) coupler with a wavelength range exceeding the O, E, S, C, L and U optical communication bands. For first time, dispersion property of MMI section is engineered using subwavelength grating structure to mitigate dependence device. present 2 × design bandwidth 450nm, almost fivefold enhancement compared conventional designs, maintaining insertion loss, power imbalance phase deviation below 1dB, 0.6dB 3°, respectively. The performed...

We demonstrate a new silicon photonic wire waveguide evanescent field (PWEF) sensor that exploits the strong of transverse magnetic mode this high-index-contrast, submicrometer-dimension waveguide. High sensitivity is achieved by using 2 mm long double-spiral structure fits within compact circular area 150 microm diameter, facilitating compatibility with commercial spotting apparatus and fabrication densely spaced arrays. By incorporating PWEF element into balanced Mach-Zehnder...

We explore, to the best of our knowledge, potential diffractionless subwavelength grating waveguides for sensing applications. show that by patterning silicon-wire field delocalization can be engineered increase sensitivity. Fully vectorial 3D-FDTD simulations confirm sensitivity enhancement, achieving sensitivities 0.83 RIU/RIU and 1.5·10(-3) RIU/nm bulk surface sensing, respectively, which compare favorably state-of-the-art waveguides.

We demonstrate a fully etched, continuously apodized fiber-to-chip surface grating coupler for the first time (to our knowledge). The device is fabricated in single-etch step and operates with TM-polarized light, achieving coupling efficiency of 3.7dB 3dB bandwidth 60nm. A subwavelength microstructure employed to generate an effective medium engineered vary strength thereby maximize efficiency, while mitigating backreflections at same time. Minimum feature size 100nm compatibility deep-UV...

We report a stationary Fourier-transform spectrometer chip implemented in silicon microphotonic waveguides. The device comprises an array of 32 Mach-Zehnder interferometers (MZIs) with linearly increasing optical path delays between the MZI arms across array. are achieved by using Si-wire waveguides arranged tightly coiled spirals compact footprint 12 mm2. Spectral retrieval is demonstrated single measurement spatial interferogram formed at output array, wavelength resolution 40 pm within...

Directional couplers are extensively used devices in integrated optics, but suffer from limited operational wavelength range. Here we use, for the first time, dispersive properties of sub-wavelength gratings to achieve a fivefold enhancement operation bandwidth silicon-on-insulator directional coupler. This approach does not compromise size or phase response device. The grating based coupler propose covers 100 nm with an imbalance ≤ 0.6 dB between its outputs, as supported by full 3D FDTD...

We present several fundamental photonic building blocks based on suspended silicon waveguides supported by a lateral cladding comprising subwavelength grating metamaterial.We discuss the design, fabrication, and characterization of waveguide bends, multimode interference devices Mach-Zehnder interferometers for 3715 -3800 nm wavelength range, demonstrated first time in this platform.The propagation loss 0.82 dB/cm is reported, some lowest yet achieved range.These results establish direct...

Abstract Nanophotonics finds ever broadening applications requiring complex components with many parameters to be simultaneously designed. Recent methodologies employing optimization algorithms commonly focus on a single performance objective, provide isolated designs, and do not describe how the design influence device behaviour. Here we propose demonstrate machine-learning-based approach map characterize multi-parameter space of nanophotonic components. Pattern recognition is used reveal...

Fiber-chip edge couplers are extensively used in integrated optics for coupling of light between planar waveguide circuits and optical fibers.In this work, we report on a new fiber-chip coupler concept with large mode size silicon photonic wire waveguides.The allows direct conventional cleaved fibers while circumventing the need lensed fibers.The is designed 220 nm silicon-on-insulator (SOI) platform.It exhibits an overall efficiency exceeding 90%, as independently confirmed by 3D...

Surface grating couplers are fundamental components in chip-based photonic devices to couple light between integrated circuits and optical fibers. In this work, we report on a coupler with sub-decibel experimental coupling efficiency using single etch process standard 220-nm silicon-on-insulator (SOI) platform. We specifically demonstrate subwavelength metamaterial refractive index engineered nanostructure backside metal reflector, the measured peak fiber-chip of -0.69 dB (85.3%) 3 bandwidth...