High performance Bragg gratings in chalcogenide glass rib waveguides written with a modified Sagnac interferometer: fabrication and characterization

We report high performance Bragg gratings in As₂S₃ chalcogenide glass rib waveguides, written with a modified Sagnac interferometer for the first time. Grating growth dynamics obtained from an in-situ monitoring system are presented and analyzedM. Shokooh-Saremi, V. G. Ta’eed, N. J. Baker, I. C. M. Littler, D. J. Moss, B. J. Eggleton, Y. Ruan and B. Luther-Davie

Long, low loss etched As2S3 chalcogenide waveguides for all-optical signal regeneration

We report on the fabrication and optical properties of etched highly nonlinear As2S3 chalcogenide planar rib waveguides with lengths up to 22.5 cm and optical losses as low as 0.05 dB/cm at 1550 nm - the lowest ever reported. We demonstrate strong spectral broadening of 1.2 ps pulses, in good agreement with simulations, and find that the ratio of nonlinearity and dispersion linearizes the pulse chirp, reducing the spectral oscillations caused by self-phase modulation alone. When combined with a spectrally offset band-pass filter, this gives rise to a nonlinear transfer function suitable for all-optical regeneration of high data rate signals

Self-phase modulation-based integrated optical regeneration in chalcogenide waveguides

Copyright © 2006 IEEEWe demonstrate integrated all-optical 2R regenerators based on Kerr optical nonlinearities (subpicosecond response) in chalcogenide glass waveguides with integrated Bragg grating filters. By combining a low loss As₂S₃ rib waveguide with an in-waveguide photo-written Bragg grating filter, we realize an integrated all-optical 2R signal regenerator with the potential to process bit rates in excess of 1 Tb/s. The device operates using a combination of self phase modulation induced spectral broadening followed by a linear filter offset from the input centerwavelength.A nonlinear power transfer curve is demonstrated using 1.4 ps pulses, sufficient for suppressing noise in an amplified transmission link. We investigate the role of dispersion on the device transfer characteristics, and discuss future avenues to realizing a device capable of operation at subwatt peak power levels.Vahid G. Ta’eed, Mehrdad Shokooh-Saremi, Libin Fu, Ian C. M. Littler, David J. Moss, Martin Rochette, Benjamin J. Eggleton, Yinlan Ruan, and Barry Luther-Davie

Integrated all-optical chalcogenide waveguide pulse regenerator: experiment and modeling

Copyright © 2005 IEEEV.G. Ta’eed, M. Shokooh-Saremi, L.B. Fu, D.J. Moss, M. Rochette, I.C.M. Littler, and B.J. Eggleto

Chalcogenide Glasses for All-optical Processing

Copyright © 2006 IEEEChalcogenide glasses, which contain S, Se or Te atoms combined with network forming elements such as Ge, As, Sb have the largest third order optical nonlinearity of any inorganic glass. As a result they are attractive candidates for fibre and waveguide devices for all-optical signal processing in the telecommunications bands. In this talk I will review our recent progress in all-optical devices such as regenerators, wavelength converters and other devices in chalcogenide glasses.B. Luther-Davies, S. J. Madden, D-Y Choi, R-P Wang, A. V. Rode, A. Prasad, R. A. Jarvis, D. Moss, B. Eggleton, C. Grillet, M. R. E. Lamont, E. Magi, V. Ta’eed, M. Shookooh-Saremi, N. Baker, I. Littler, L. Fu, M. Rochette, Y. Rua

Travelling-wave resonant four-wave mixing breaks the limits of cavity-enhanced all-optical wavelength conversion

Wave mixing inside optical resonators, while experiencing a large enhancement of the nonlinear interaction efficiency, suffers from strong bandwidth constraints, preventing its practical exploitation for processing broad-band signals. Here we show that such limits are overcome by the new concept of travelling-wave resonant four-wave mixing (FWM). This approach combines the efficiency enhancement provided by resonant propagation with a wide-band conversion process. Compared with conventional FWM in bare waveguides, it exhibits higher robustness against chromatic dispersion and propagation loss, while preserving transparency to modulation formats. Travelling-wave resonant FWM has been demonstrated in silicon-coupled ring resonators and was exploited to realize a 630-μm-long wavelength converter operating over a wavelength range wider than 60 nm and with 28-dB gain with respect to a bare waveguide of the same physical length. Full compatibility of the travelling-wave resonant FWM with optical signal processing applications has been demonstrated through signal retiming and reshaping at 10 Gb s−

Ultra-Strong and well-apodized Bragg gratings in chalcogenide rib waveguides

©2005 IEEE. Personal use of this material is permitted. However, permission to reprint/republish this material for advertising or promotional purposes or for creating new collective works for resale or redistribution to servers or lists, or to reuse any copyrighted component of this work in other works must be obtained from the IEEE.The first ultra-strong, near-perfect, raised-apodised Bragg gratings in As₂S₃ chalcogenide rib waveguides using λ=532 nm light and a modified Sagnac holographic writing setup are demonstrated. Good agreement is achieved between the experimental results and the numerical modelling of the gratings using the transfer matrix analysis for thin film structures.M. Shokooh-Saremi, V.G. Ta’eed , I.C.M. Littler , D.J. Moss, B.J. Eggleton, Y. Ruan and B. Luther-Davie

High order mode conversion via focused ion beam milled Bragg gratings in Silicon-on-Insulator Waveguides

We report the first use of focused ion beam milling to fabricate surface relief gratings in optical waveguides. We demonstrate efficient coupling to very high order modes in silicon-on-insulator waveguides and discuss the implications both for future devices based on higher order modes as well as more conventional devices based on Bragg reflection from the fundamental modePeer reviewed: YesNRC publication: Ye

Surface gratings as a diagnostic for higher order surface modes in SOI waveguides,

NRC publication: Ye