All Outputs (169)

The nonlinear fabry-pérot cavity: Complexity in a simple optical feedback system (2013)
Presentation / Conference
Patel, S., Christian, J., Bostock, C., & McDonald, G. (2013, June). The nonlinear fabry-pérot cavity: Complexity in a simple optical feedback system. Presented at College of Science & Technology Research Showcase, University of Salford

The nonlinear Fabry-Pérot (FP) cavity [see Fig. 1(a)] is a generalization of the classic diffusive Kerr slice with a single feedback mirror [1,2]. Such apparent simplicity is deceptive. Historically, analysis of the FP geometry has proved to be a non... Read More about The nonlinear fabry-pérot cavity: Complexity in a simple optical feedback system.

Coupled-waveguide arrays: Oblique injection & soliton propagation (2013)
Presentation / Conference
Christian, J., McCoy, E., & McDonald, G. (2013, June). Coupled-waveguide arrays: Oblique injection & soliton propagation. Presented at College of Science & Technology Research Showcase, University of Salford

The interaction between light beams and periodically-patterned host materials (such as coupled-waveguide arrays or photonic crystals) is a fundamental class of problem in nonlinear optics [1,2]. While oblique (off-axis) propagation effects play a cen... Read More about Coupled-waveguide arrays: Oblique injection & soliton propagation.

Algebraic soliton refraction: New wave contexts for nonlinear Snell’s law (2013)
Presentation / Conference
Yates, R., Christian, J., & McDonald, G. (2013, June). Algebraic soliton refraction: New wave contexts for nonlinear Snell’s law. Presented at College of Science & Technology Research Showcase, University of Salford

The refraction of light waves at planar interfaces is a problem of fundamental interest to the optics community. To date, our Snell’s law-type analyses have considered only families of hyperbolic solitons – robust nonlinear beams that are strongly (e... Read More about Algebraic soliton refraction: New wave contexts for nonlinear Snell’s law.

Refraction at interfaces with X(5) nonlinearity: Snell’s law & Goos-Hänchen shifts (2013)
Presentation / Conference
McCoy, E., Christian, J., & McDonald, G. (2013, June). Refraction at interfaces with X(5) nonlinearity: Snell’s law & Goos-Hänchen shifts. Presented at College of Science & Technology Research Showcase, University of Salford

In this presentation, we give the first detailed overview of spatial soliton refraction at the planar interface between materials whose nonlinear polarization has contributions from both X(3)and X(5)susceptibilities [1]. The governing equation is of... Read More about Refraction at interfaces with X(5) nonlinearity: Snell’s law & Goos-Hänchen shifts.

Coupled spatiotemporal waves: New paradigms in vector soliton physics (2013)
Presentation / Conference
Ashley, J. T., Christian, J., & McDonald, G. (2013, June). Coupled spatiotemporal waves: New paradigms in vector soliton physics. Presented at College of Science & Technology Research Showcase, University of Salford

In this presentation, we propose a novel spatiotemporal generalization of Menyuk’s classic equations [1] describing the propagation of two nonlinearly-coupled waves in a dispersive optical system (such as a fibre or planar waveguide). Our approach is... Read More about Coupled spatiotemporal waves: New paradigms in vector soliton physics.

The spatiotemporal ginzburg-landau equation: Dissipative solitons & stability (2013)
Presentation / Conference
Bresnahan, D., Christian, J., & McDonald, G. (2013, June). The spatiotemporal ginzburg-landau equation: Dissipative solitons & stability. Presented at College of Science & Technology Research Showcase, University of Salford

The complex Ginzburg-Landau (GL) equation describes universal wave propagation in dispersive systems that also exhibit competition between amplification and dissipation [1,2]. The balance between dispersive effects (group-velocity dispersion and self... Read More about The spatiotemporal ginzburg-landau equation: Dissipative solitons & stability.

Helmholtz bright spatial solitons and surface waves at power-law optical interfaces (2012)
Journal Article
Christian, J., McCoy, E., McDonald, G., Sanchez-Curto, J., & Chamorro-Posada, P. (2012). Helmholtz bright spatial solitons and surface waves at power-law optical interfaces. Journal of Atomic, Molecular, and Optical Physics, 2012, 137967. https://doi.org/10.1155/2012/137967

We consider arbitrary-angle interactions between spatial solitons and the planar boundary between two optical materials with a single power-law nonlinear refractive index. Extensive analysis has uncovered a wide range of new qualitative phenomena in... Read More about Helmholtz bright spatial solitons and surface waves at power-law optical interfaces.

Time domain analysis of Helmholtz soliton propagation using the TLM method (2012)
Journal Article
Chamorro-Posada, P., & McDonald, G. (2012). Time domain analysis of Helmholtz soliton propagation using the TLM method. Journal of Nonlinear Optical Physics and Materials, 21(03), https://doi.org/10.1142/S0218863512500312

The transmission line matrix method is used to study Helmholtz solitons as solutions of the two-dimensional time-domain Maxwell equations in nonlinear media. This approach permits to address, in particular, the propagation and intrinsic stability pr... Read More about Time domain analysis of Helmholtz soliton propagation using the TLM method.

Wave envelopes with second-order spatiotemporal dispersion: II. Modulational instabilities and dark Kerr solitons (2012)
Journal Article
II. Modulational instabilities and dark Kerr solitons. Physical Review A, 86(2), 023839. https://doi.org/10.1103/PhysRevA.86.023839

A simple scalar model for describing spatiotemporal dispersion of pulses, beyond the classic “slowly-varying envelopes + Galilean boost” approach, is studied. The governing equation has a cubic nonlinearity and we focus here mainly on contexts with... Read More about Wave envelopes with second-order spatiotemporal dispersion: II. Modulational instabilities and dark Kerr solitons.

Spatial solitons at interfaces: nonparaxial refraction & giant Goos-Hänchen shifts (2012)
Presentation / Conference
nonparaxial refraction & giant Goos-Hänchen shifts. Poster presented at College of Science and Technology Research Showcase Day, University of Salford, Greater Manchester, UK

The behaviour of light at interfaces underpins, in an essential way, the entire field of optics: almost all technological device designs and architectures rely on the interplay between material mismatches (that define the interface) and the 'degree o... Read More about Spatial solitons at interfaces: nonparaxial refraction & giant Goos-Hänchen shifts.

Helmholtz spatial solitons: towards a theory of ultranarrow optical beams (2012)
Presentation / Conference
Walsh, T., McDonald, G., & Christian, J. (2012, June). Helmholtz spatial solitons: towards a theory of ultranarrow optical beams. Poster presented at College of Science and Technology Research Showcase Day, University of Salford, Greater Manchester, UK

Spatial optical solitons are self-localizing and self-stabilizing beams of light that propagate with a stationary (invariant) intensity profile. Such nonlinear wave states may arise when a beam's natural tendency to diffract is exactly compensated by... Read More about Helmholtz spatial solitons: towards a theory of ultranarrow optical beams.

Vector spatial solitons: off-axis nonparaxiality in coupled Helmholtz equations (2012)
Presentation / Conference
in coupled Helmholtz equations. Poster presented at College of Science and Technology Research Showcase Day, University of Salford, Greater Manchester, UK

Vector spatial solitons are complex optical beams with several distinct components. These components (which may be bright-like and/or dark-like) are localized in space and tend to overlap strongly in the propagation plane, thereby allowing the interp... Read More about Vector spatial solitons: off-axis nonparaxiality in coupled Helmholtz equations.

Spatiotemporal pulse propagation: connections to special relativity theory (2012)
Presentation / Conference
connections to special relativity theory. Poster presented at College of Science and Technology Research Showcase Day, University of Salford, Greater Manchester, UK

We propose a more complete model for describing the evolution of scalar optical pulses in nonlinear waveguides. The electromagnetic wave envelope u satisfies a dimensionless spatiotemporal governing equation that is of a fully-second-order form. Wit... Read More about Spatiotemporal pulse propagation: connections to special relativity theory.

Helmholtz dark solitons: oblique propagation, saturable materials & bistability (2012)
Presentation / Conference
oblique propagation, saturable materials & bistability. Poster presented at College of Science and Technology Research Showcase Day, University of Salford, Greater Manchester, UK

Dark spatial optical solitons comprise a uniform background wave that is modulated by an obliquely-propagating 'dip' in the light intensity profile. Appearing throughout nonlinear science, these universal entities possess a phase topology that endows... Read More about Helmholtz dark solitons: oblique propagation, saturable materials & bistability.

Instabilities & boundary conditions: fractal mode patterns in kaleidoscope lasers (2012)
Presentation / Conference
fractal mode patterns in kaleidoscope lasers. Poster presented at College of Science and Technology Research Showcase Day, University of Salford, Greater Manchester, UK

The multi-scale - or fractal - nature of transverse modes in one-dimensional (1D) unstable cavity lasers has been known since the late 1990s [1]. Early collaborations with some members of our Group demonstrated that the origin of fractality (which de... Read More about Instabilities & boundary conditions: fractal mode patterns in kaleidoscope lasers.

Helmholtz bright and black soliton splitting at nonlinear interfaces (2012)
Journal Article
Sanchez-Curto, J., Chamorro-Posada, P., & McDonald, G. (2012). Helmholtz bright and black soliton splitting at nonlinear interfaces. Physical Review A, 85, https://doi.org/10.1103/PhysRevA.85.013836

Soliton breakup occurring at the planar boundary separating two Kerr focusing and defocusing media is analyzed within the framework of the Helmholtz theory where the full angular content of the problem is preserved. We show that the number of soliton... Read More about Helmholtz bright and black soliton splitting at nonlinear interfaces.

Wave envelopes with second-order spatiotemporal dispersion : I. Bright Kerr solitons and cnoidal waves (2012)
Journal Article
I. Bright Kerr solitons and cnoidal waves. Physical Review A, 86(2), 023838. https://doi.org/10.1103/PhysRevA.86.023838

We propose a simple scalar model for describing pulse phenomena beyond the conventional slowly-varying envelope approximation. The generic governing equation has a cubic nonlinearity and we focus here mainly on contexts involving anomalous group-vel... Read More about Wave envelopes with second-order spatiotemporal dispersion : I. Bright Kerr solitons and cnoidal waves.

Spatiotemporal dispersion and wave envelopes with relativistic and pseudorelativistic characteristics (2012)
Journal Article
Christian, J., McDonald, G., Hodgkinson, T., & Chamorro-Posada, P. (2012). Spatiotemporal dispersion and wave envelopes with relativistic and pseudorelativistic characteristics. Physical Review Letters, 108(3), 034101-1. https://doi.org/10.1103/PhysRevLett.108.034101

A generic nonparaxial model for pulse envelopes is presented. Classic Schro¨dinger-type descriptions of
wave propagation have their origins in slowly-varying envelopes combined with a Galilean boost to the
local time frame. By abandoning these two... Read More about Spatiotemporal dispersion and wave envelopes with relativistic and pseudorelativistic characteristics.

Spontaneous spatial fractal pattern formation in absorptive systems (2012)
Journal Article
Huang, J. G., Christian, J. M., & McDonald, G. S. (2012). Spontaneous spatial fractal pattern formation in absorptive systems. Journal of Nonlinear Optical Physics and Materials, 21(2), 1-9. https://doi.org/10.1142/S021886351250018X

We predict, for the first time to our knowledge, that purely-absorptive nonlinearity can support spontaneous spatial fractal pattern formation. A passive optical ring cavity with a thin slice of saturable absorber is analyzed. Linear stability analys... Read More about Spontaneous spatial fractal pattern formation in absorptive systems.

Two-colour optical fields: modulational instabilities and vector spatial solitons (2011)
Presentation / Conference
Bostock, C., Christian, J., & McDonald, G. (2011, November). Two-colour optical fields: modulational instabilities and vector spatial solitons. Presented at 2nd CSE Doctoral School Postgraduate Research Conference, University of Salford, Greater Manchester

The propagation of a light beam at a single optical frequency – or colour – in a Kerr-type planar waveguide is an elementary configuration in photonics [1,2]. Under two classic assumptions: (i) that the transverse extent of the
beam is much greater... Read More about Two-colour optical fields: modulational instabilities and vector spatial solitons.