Oxford, United Kingdom
Oxford, United Kingdom

Time filter

Source Type

Sciancalepore C.,CEA Grenoble | Lycett R.J.,Photon Design Ltd. | Dallery J.A.,Vistec Electronic Beam GmbH | Pauliac S.,CEA Grenoble | And 7 more authors.
IEEE Photonics Technology Letters | Year: 2015

In this letter, we report about design, fabrication, and testing of echelle grating (EG) demultiplexers in the O-band (1.31-μ m) for silicon-based photonic integrated circuits. In detail, flat band perfectly chirped EGs and two-point stigmatic EGs on the 300-nm thick silicon-on-insulator platform designed for 4 × 800-GHz spaced wavelength-division multiplexing featuring a low average crosstalk (-30 dB), a precise channel spacing, optimized interchannel uniformity (0.7 dB) and insertion losses (3-3.5 dB) are presented. Wafer-level statistical performance analysis shows the EG spectral response to be stable over the wafer in terms of crosstalk, channel spacing, and bandwidth with minimal wavelength dispersion (<0.8 nm), thus highlighting the intrinsic robustness of high-order gratings and chosen fab pathways as well as the full reliability of 3-D vectorial modeling tools. © 1989-2012 IEEE.


Grant
Agency: Cordis | Branch: FP7 | Program: CP | Phase: ICT-2009.3.7 | Award Amount: 12.99M | Year: 2010

The objective of PARADIGM is to effect a fundamental change in the way photonic integrated circuits (PICs) based on indium phosphide (InP) are designed and manufactured in Europe, with the aim of reducing the costs of design, development and manufacture by more than an order of magnitude and making more complex and capable designs possible than ever before.\n\nThe key step is to develop a generic platform technology for application-specific PICs. This will be achieved by adopting a similar methodology in the field of photonics to the one that has been so successful in microelectronics. The new approach developed in PARADIGM will be indispensable in creating a sustainable business sector with potential for significant future growth.\n\nPARADIGM addresses the whole product development chain from concept, through design and manufacturing to application. It will establish library-based design, coupled with standardized technology process flows and supported by sophisticated design tools. Our goal is to develop technical capability at the platform level, rather than at the level of individual designs, greatly reducing the cost and time required to bring a new component into production, whilst allowing the designer great freedom for creativity at the circuit level.\n\nTo establish a generic, design-rule and library-based methodology for photonic ICs is an ambitious and demanding task, which could only be contemplated with a consortium possessing a wide range of complementary skills. PARADIGM has brought together just such a collaboration of Europes key players in the fields of III-V semiconductor manufacturing, PIC design and applications, photonic CAD, packaging and assembly.\n\nThe project will verify the potential of the generic approach by fabricating a number of InP PICs, addressing a range of applications in communications, sensors, data processing and biomedical systems, at a level of complexity and performance that will define the state of the art.


Grant
Agency: Cordis | Branch: FP7 | Program: CP-TP | Phase: NMP-2008-3.5-1 | Award Amount: 5.64M | Year: 2009

The objective of EuroPIC is no less than to effect a fundamental change in the way applications based on photonic integrated circuits (PICs) are designed and manufactured in Europe. The key development is to facilitate access by small companies (SMEs) to development and manufacturing of photonic micro-systems in the form of advanced but very cost effective PICs. EuroPIC can bring forth a new production paradigm to forge a sustainable business sector with the potential for very significant future growth. This will be done by developing a generic technology that is capable of realising complex PICs from a small set of basic building blocks. The programme adopts a holistic approach addressing the whole production chain from idea, via proof of concept, design and prototype to product and application. The consortium will carry out research into manufacturing methods and high-throughput processes which will lead to an open-access industrial generic foundry production capability for Europe. It will demonstrate the potential of the generic approach by fabricating a number of Application Specific PICs (ASPICs) with a record combination of complexity and performance, for a wide range of applications in telecommunications, sensors, data communications, medical systems, metrology and consumer photonics. The consortium is in an excellent position to carry out this ambitious task. It includes Europes key players, a mix of SMEs, industry and academic partners, in the fields of component manufacturing, PIC design and applications, photonic CAD, and packaging. Further, EuroPIC is building a strong User Group, many of them SMEs, with committed users from different application fields, which will be actively involved in introducing cost-effective ASPICs in a variety of novel applications, providing Europe with a competitive advantage over the US and the Far East.


Grant
Agency: Cordis | Branch: FP7 | Program: CP | Phase: ICT-2009.3.8 | Award Amount: 3.67M | Year: 2010

The aim of this project is to transfer the latest advances in plasmonics achieved in the visible to the mid-IR. The main objectives of the project are (1) to look at the fundamental limits and develop new simulation tools for plasmons in the mid-IR, (2) to develop plasmon enhanced surfaces for spectroscopic chemical sensing (SCS), and (3) to use plasmon enhanced surfaces for light harvesting technology. The result of the project will include new software, SCS surfaces for infra-red spectroscopy and smart, cheaper, mid-IR photodetectors. \nThe term plasmonics refers to the investigation, development and application of enhanced electromagnetic properties of metallic (nano-) structures and is starting to find applications in a range of photonic devices such as VCSELs and high speed photodetectors. While the promise of plasmonics photonic components in the visible and NIR is very promising, this project will exploit the huge potential for plasmonics in the IR (i.e. the 1.6-16 m range) that could be truly disruptive.\nIn the mid-IR (a) plasmon losses are much lower than in the visible so the range of possible devices is much larger (b) this area is largely unexplored for applied plasmonics, and (c) IR technology is undergoing a quiet revolution due to key advances such as such room temperature Quantum Cascade Lasers and miniature Fourier transform spectrometers (FTS). This project will help launch the IR revolution by enabling both SCS surfaces and better mid-IR detectors.\nPLAISIR will develop SCS with sensitivity more than 200 times larger than that of a simple surface. This will be combined with microfluidics and integrated into a FTS. The project will work with both InGaAs and HgCdTe photodetectors, by using LHT to improve their noise performance, and tailor their spectral and polarization response. \nThis project includes 4 major actors in fundamental and applied plasmon research, 3 SMEs and an external advisory board made up of strategic end users and key academics


Weismann M.,University College London | Weismann M.,Photon Design Ltd. | Gallagher D.F.G.,Photon Design Ltd. | Panoiu N.C.,University College London
Journal of the Optical Society of America B: Optical Physics | Year: 2015

We introduce a versatile numerical method for modeling light diffraction in periodically patterned photonic structures containing quadratically nonlinear non-centrosymmetric optical materials. Our approach extends the generalized source method to nonlinear optical interactions by incorporating the contribution of nonlinear polarization sources to the diffracted field in the algorithm. We derive the mathematical formalism underlying the numerical method and introduce the Fourier-factorization suitable for nonlinear calculations. The numerical efficiency and runtime characteristics of the method are investigated in a set of benchmark calculations. The results corresponding to the fundamental frequency are compared to those obtained froma reference method and the beneficial effects of the modified Fourier-factorization rule on the accuracy of the nonlinear computations is demonstrated. To illustrate the capabilities of our method, we employ it to demonstrate strong enhancement of second-harmonic generationon one- and two-dimensional optical gratings resonantly coupled to a slab waveguide. Our method can be easily extended to other types of nonlinear optical interactions by simply incorporating the corresponding nonlinear polarization sources in the algorithm. © 2015 Optical Society of America.


Weismann M.,University College London | Weismann M.,Photon Design Ltd. | Gallagher D.F.G.,Photon Design Ltd. | Panoiu N.C.,University College London
Proceedings of SPIE - The International Society for Optical Engineering | Year: 2014

We present a new numerical method for the analysis of second-harmonic generation (SHG) in one-and twodimensional (1D, 2D) diffraction gratings with arbitrary profile made of non-centrosymmetric optical materials. Our method extends the generalized source method (GSM), which is a highly efficient alternative to the conventional Fourier modal method, to quadratically nonlinear diffraction gratings. The proposed method consists of a two-stage algorithm. Initially, the electromagnetic field at the fundamental frequency is computed in order to obtain the second-harmonic polarization using the known second-order nonlinear susceptibility. Then the optical field at the second-harmonic frequency is computed using this polarization as an additional source term in the GSM. We show how to integrate this source term into the GSM framework without changing the structure of the basic algorithm. We use the proposed algorithm to investigate a doubly resonant mechanism that leads to strong enhancement of SHG in a nonlinear 2D circular GaAs grating mounted on top of a GaAs slab waveguide. We design this optical device such that slab waveguide modes at the fundamental and second-harmonic are simultaneously excited and phase matched by the grating. The numerically obtained resonance frequencies show good agreement with analytically computed resonance frequencies of the unperturbed slab waveguide. © 2014 SPIE.


Weismann M.,University College London | Weismann M.,Photon Design Ltd | Panoiu N.C.,University College London
2014 8th International Congress on Advanced Electromagnetic Materials in Microwaves and Optics, METAMATERIALS 2014 | Year: 2014

We introduce an expansion of the Fourier modal method for the analysis of periodic structures with oblique walls by using a three-dimensional normal vector field for the correct Fourier series factorization of products of discontinuous functions. Our numerical tests show that the improved method leads to faster convergence as compared to conventional two-dimensional decomposition rules. © 2014 IEEE.


Timbrell D.,University College London | Weismann M.,University College London | Weismann M.,Photon Design Ltd | Braz N.V.S.,University College London | And 2 more authors.
2015 9th International Congress on Advanced Electromagnetic Materials in Microwaves and Optics, METAMATERIALS 2015 | Year: 2015

Toroidal multipoles are a class of electromagnetic moments which must be separately considered from the electric and magnetic multipoles in a multipole decomposition of the sources of the electromagnetic field. We present a plasmonic metamaterial exhibiting a resonant enhancement of the lowest order toroidal multipole at the second harmonic (SH). The total transmission, reflection and absorption spectra at the fundamental frequency (FF) show that the enhanced nonlinear optical response of the toroidal metamaterial is due to an excitation of an electromagnetic resonance at the FF. This connection is also illustrated by the spectral characteristics of the power radiated in the direction of transmission at the SH as well as the frequency dependence of the electric, magnetic, and toroidal dipole radiation at the SH. © 2015 IEEE.


Weismann M.,University College London | Weismann M.,Photon Design Ltd | Gallagher D.F.G.,Photon Design Ltd | Panoiu N.C.,University College London
Journal of Optics (United Kingdom) | Year: 2015

The rigorous coupled-wave analysis (RCWA) is one of the most successful and widely used methods for modeling periodic optical structures. It yields fast convergence of the electromagnetic far-field and has been adapted to model various optical devices and wave configurations. In this article, we investigate the accuracy with which the electromagnetic near-field can be calculated by using RCWA and explain the observed slow convergence and numerical artifacts from which it suffers, namely unphysical oscillations at material boundaries due to the Gibbs phenomenon. In order to alleviate these shortcomings, we also introduce a mathematical formulation for accurate near-field calculation in RCWA, for one- and two-dimensional straight and slanted diffraction gratings. This accurate near-field computational approach is tested and evaluated for several representative test-structures and configurations in order to illustrate the advantages provided by the proposed modified formulation of the RCWA. © 2015 IOP Publishing Ltd.


Wu L.,Zhejiang University | He J.-J.,Zhejiang University | Gallagher D.,Photon Design Ltd
Journal of the Optical Society of America B: Optical Physics | Year: 2015

We investigate the static and dynamic characteristics of the widely tunable V-cavity semiconductor laser using the time-domain traveling-wave method. The theoretical model is presented. The simulation results are compared with experimental data for an all-active V-cavity laser, and good agreements are obtained. To improve the device performance, a new device structure with passive tuning waveguides is designed. The numerical results show that 21 channels can be achieved by single electrode tuning using carrier injection effect with two cavities of 420 and 440 μm long. Dynamic wavelength switching between different channels is simulated. Mode competition is observed during the transient and the switching delay time varies from 3 to 18.5 ns for different switching paths. A simple algorithm for quasi-continuous tuning is developed for the first time by varying the injection currents on the channel selector electrode and the fine-tuning electrode synchronously. A quasi-continuous tuning of 16.8 nm is achieved with a current variation of less than 20 mA on each electrode. For direct modulation characteristics, small signal response simulation is carried out by an impulse current injection with a fast Fourier transform algorithm, and a 3 dB bandwidth of 7 GHz is obtained when biased at 100 mA. Moreover, 2.5 and 10 Gb/s direct intensity modulation are also demonstrated. The simulation results show great potential for the compact and low-cost tunable laser to be used for wavelength-agile access and data center networks, as well as biomedical applications. © 2015 Optical Society of America.

Loading Photon Design Ltd. collaborators
Loading Photon Design Ltd. collaborators