A5054236919- Optical Network Technologies
- Semiconductor Lasers and Optical Devices
- Photonic and Optical Devices
- Advanced Photonic Communication Systems
- Advanced Fiber Laser Technologies
- Photonic Crystal and Fiber Optics
- Spectroscopy and Laser Applications
- Asymmetric Synthesis and Catalysis
- Semiconductor Quantum Structures and Devices
- nanoparticles nucleation surface interactions
- Advanced Materials Characterization Techniques
- Magnetic Properties of Alloys
- X-ray Diffraction in Crystallography
- Neural Networks and Reservoir Computing
- Catalysis and Oxidation Reactions
- Magnetic properties of thin films
- Asymmetric Hydrogenation and Catalysis
- Synthesis and Catalytic Reactions
- Crystallization and Solubility Studies
- Force Microscopy Techniques and Applications
- Solid State Laser Technologies
- Laser Design and Applications
- High Temperature Alloys and Creep
- Intermetallics and Advanced Alloy Properties
- Catalytic C–H Functionalization Methods
Kelada Pharmachem (Ireland)
2015-2025
Eblana Photonics (Ireland)
2013-2024
Cardiff University
2023
22q11 Ireland
2020
University of Delaware
2013-2017
Trinity College Dublin
1993-2016
University of Southampton
2013
Enterprise Ireland
2007
Seagate (United Kingdom)
2005
University College Dublin
2002
The first demonstration of a hollow core photonic bandgap fiber (HC-PBGF) suitable for high-rate data transmission in the 2 µm waveband is presented.The has record low loss this wavelength region (4.5 dB/km at 1980 nm) and >150 nm wide surface-mode-free window center bandgap.Detailed analysis optical modes their propagation along fiber, carried out using time-of-flight technique conjunction with spatially spectrally resolved (S ) imaging, provides clear evidence that HC-PBGF can be operated...
We show for the first time 100 Gbit/s total capacity at 2 µm waveband, using 4 × 9.3 4-ASK Fast-OFDM direct modulation and 15.7 NRZ-OOK external modulation, spanning a 36.3 nm wide wavelength range.WDM transmission was successfully demonstrated over 1.15 km of low-loss hollow core photonic bandgap fiber (HC-PBGF) 1 solid (SCF).We conclude that OSNR penalty associated with SCF is minimal, while ~1-2 dB observed after HC-PBGF probably due to mode coupling higher-order modes.
The 2-μm wave band is emerging as a potential new window for optical telecommunications with several distinct advantages over the traditional 1.55 μm region. First of all, hollow-core photonic gap fiber (HC-PBGF) an transmission candidate ultra-low nonlinearity and lowest latency (0.3% slower than light propagating in vacuum) that has its minimum loss within wavelength band. Second, thulium-doped amplifier operates this spectral region provides significantly more bandwidth erbium-doped...
We report on the generation of picosecond pulses at 2 μm directly from a gain-switched discrete-mode diode laser and their amplification in multistage thulium-doped fiber amplifier chain. The system is capable operating repetition rates range MHz-1.5 GHz without change configuration, delivering high-quality 33 ps with up to 3.5 μJ energy 100 kW peak power, as well 18 W average power. These results represent major technological advance 1 order magnitude increase power pulse compared existing...
Wafer-level mass production of photonic integrated circuits (PIC) has become a technological mainstay in the field optics and photonics, enabling many novel disrupting wide range existing applications. However, scalable packaging system assembly still represents major challenge that often hinders commercial adoption PIC-based solutions. Specifically, chip-to-chip fiber-to-chip connections rely on so-called active alignment techniques, where coupling efficiency is continuously measured...
Ex-facet, free-running low linewidth (∼100 kHz), singlemode laser emission is demonstrated using cost, regrowth-free ridge waveguide discrete mode Fabry-Pérot diode chips. These narrow linewidths are observed even at powers as 500 µW.
A discrete-mode laser diode fabricated in the InGaAs/InP multiple quantum-well system and emitting single mode at λ = 2 μm is reported. The had an ex-facet output power >;5 mW 25 °C operated mode-hop free temperature range -5 °C-55 °C.
Herein is reported the development of a new process to manufacture (S)-pregabalin. The method comprises six steps, run under catalysis recyclable polymer bound phase transfer catalyst, and afforded (S)-pregabalin in overall 54% yield, starting from building blocks acetylacetone, isovaleraldehyde, nitromethane.
Progress on advanced active and passive photonic components that are required for high-speed optical communications over hollow-core bandgap fiber at wavelengths around 2 μm is described in this paper. Single-frequency lasers capable of operating 10 Gb/s covering a wide spectral range realized. A comparison made between waveguide surface normal photodiodes with the latter showing good sensitivity up to 15 Gb/s. Passive waveguides, 90° hybrids, arrayed grating 100-GHz channel spacing...
We show, for the first time, dense WDM (8×20 Gbit/s) transmission at 2 μm enabled by advanced modulation formats (4-ASK Fast-OFDM) and development of key components, including a new arrayed waveguide grating (AWGr) μm. The AWGr shows -12.8±1.78 dB excess loss with an 18-dB extinction ratio thermal tunability 0.108 nm/°C.
Indole heterocycles have an established reactivity, and these compounds are H-bond donors via a peculiar non-basic NH. However, the indole core has been scarcely employed in organocatalysis, with only few examples relevant to electrophilic halogenation reported. To expand range of potential transformations achievable catalysis, we designed set new organic species incorporating core, alongside three privelaged chiral moieties found many known organocatalysts, namely quaternary ammonium salt,...
Abstract The ability to generate high-speed on–off-keyed telecommunication signals by directly modulating a semiconductor laser’s drive current was one of the most exciting prospective applications nascent field laser technology throughout 1960s. Three decades progress led commercialization 2.5 Gbit s −1 -per-channel submarine fibre optic systems that drove growth internet as global phenomenon. However, detrimental frequency chirp associated with direct modulation forced industry use...
The wavelength spectra of ridge waveguide Fabry Perot lasers can be modified by perturbing the effective refractive index guided mode along very small sections laser cavity. One way locally lasing is etching features into such that each feature has a overlap with transverse field profile unperturbed mode, consequently most light in cavity unaffected these perturbations. A proportion propagating however reflected at boundaries between perturbed and sections. Suitable positioning interfaces...
A novel widely tunable laser diode is proposed and demonstrated. Mode selection occurs by etching perturbing slots into the ridge. two-section device realized with different slot patterns in each section allowing Vernier tuning. The operates at 1.3 mum achieves a maximum output power of 10 mW. discontinuous tuning range 30 nm was achieved side mode suppression greater than dB. Wavelength switching times approximately 1.5 ns between number wavelength channels separated 7 have been
Get PDF Email Share with Facebook Tweet This Post on reddit LinkedIn Add to CiteULike Mendeley BibSonomy Citation Copy Text R. Weerasuriya, S. Sygletos, K. Ibrahim, Phelan, J. O'Carroll, B. Kelly, O'Gorman, and A. D. Ellis, "Generation of frequency symmetric signals from a BPSK input for Phase Sensitive Amplification," in Optical Fiber Communication Conference, OSA Technical Digest (CD) (Optica Publishing Group, 2010), paper OWT6. Export BibTex Endnote (RIS) HTML Plain alert Save article
Cost effective lasers meeting the linewidth requirements for coherent communication systems are a key element in reducing overall cost of future systems. We report on monolithic devices with linewidths as low 138 kHz which operate narrow linewidth, single wavelength mode high sidemode suppression ratio over wide temperature tuning range -10 °C < T 110 °C. A variation only 23 was measured at constant emitted power 4 mW device is varied 0 85
The first demonstration of a hollow core photonic bandgap fiber suitable for high-rate data transmission at 2µm is presented. Using custom built Thulium doped amplifier, error-free 8Gbit/s in an optically amplified channel 2008nm reported the time.
This paper demonstrates how the PIXAPP Photonics Packaging Pilot Line uses its extensive packaging capabilities across European partner network to design and assemble a highly integrated silicon photonic-based optical transceiver. The processes used are based on PIXAPP's open access rules or Assembly Design Kit (ADK). transceiver was designed have Tx Rx elements single photonic chip, together with flipchip control electronics, hybrid laser micro-optics. on-chip micro-optics enable...
The authors present the design and characterization of a novel integrated two-section discrete mode index patterned diode laser source. two slotted regions etched into ridge waveguide are formed in same fabrication step as ridge, thus avoiding requirement for complex lithography regrowth steps. is encased temperature-controlled butterfly package, which simplifies static dynamic measurements. Initial this shows that injection, from master to slave laser, enhances slave's emission side-mode...
Discrete-mode lasers fabricated in the AlGaInAs/InP multiple quantum well (MQW) system and emitting around λ=1.3 µm operate efficiently at high temperatures exhibit mode-hop-free singlemode operation temperature, T, range −40°C<T<95°C.
Return-to-Zero (RZ) and Non-Return-to-Zero (NRZ) Differential Phase Shift Keyed (DPSK) systems require cheap optimal transmitters for widespread implementation. The authors report on a gain switched Discrete Mode (DM) laser that can be employed as cost efficient transmitter in 10.7 Gb/s RZ DPSK system compare its performance to of Distributed Feed-Back (DFB) laser. Experimental results show the DM readily provides error free receiver sensitivity -33.1 dBm Gbit/s system. standard DFB other...
An edge-coupled high-speed photodiode based on strained InGaAs quantum wells for detection at 2000nm is demonstrated. The fabricated device shows a leakage current as low 120nA −3V bias voltage and responsivity of around 0.3A/W 2000nm. butterfly packaging the presented which 3dB bandwidth more than 10GHz. similar performance 1550nm.
The design and measured performance characteristics of a range index-patterned diode laser sources are presented. These devices incorporate slotted regions etched into the ridge waveguide, which formed in same fabrication step as ridge, thus avoiding requirement for complex lithography regrowth steps. We first demonstrate that index profile single multimode can be obtained directly from an inverse problem solution based on perturbative calculation threshold gain longitudinal modes cavity....
We report on high-energy nanosecond-pulsed fiber master oscillator power amplifier (MOPA) systems seeded by semiconductor laser diodes at 2 μm incorporating arbitrary pulse-shaping capabilities. Two MOPA systems, one based direct diode modulation and the second using additional electro-optic modulator (EOM) shaping, are investigated, with up to 0.5 mJ (25 kHz) 1.0 (12.5 pulse energies achieved, respectively, for 100 ns pulses user-defined shapes. Our results indicate that further energy...
We describe a method of tailoring the laser spectrum Fabry-Perot (FP) diodes using spatially varying refractive index. The cavity geometry is determined by perturbative transmission matrix calculation threshold gain longitudinal modes and solution corresponding inverse problem. Single-mode FP lasers with predetermined wavelength, two-color mode spacing in terahertz region are designed experimentally demonstrated.