Research Highlights

Fundamental research highlights
The Nonlinear Physics Group at ANU has been active in exploring, by experimental observation and theoretical analysis, a range of novel physical phenomena in optically induced lattices. These include the first observation of two-dimensional Bloch oscillations and Zener tunneling, one- and two dimensional optical gap solitons and their enhanced mobility and tunable negative refraction.

The outcomes of this work are relevant to experiments in the 3D lattices fabricated at Swinburne University, and over the coming year we will conduct experiments that build on the superprism observations to explore these sophisticated propagation effects.

The Centre depends heavily on sophisticated numerical approaches to modeling wave propagation in micro-structures including photonic crystal fibres and two dimensional photonic crystals. During the year the theory teams at Sydney and UTS developed a novel technique able to model modes in genuinely infinite photonic structures. Referred to as the fictitious source superposition method, the technique was used to demonstrate unambiguously that the fundamental mode of a micro-structured optical fibre has no cutoff, thus resolving a problem of some considerable international debate.

Our photonic crystal simulation tools (CUDOS MOF Utilities) have been extended to study photonic crystal fibres with holes coated with arbitrary materials. Using this software and through analytic work, the Sydney group demonstrated novel, hybrid mechanisms of guidance of light in these fibres, and demonstrated that, when the holes are coated with metal, plasmonic resonances can be excited inside the fibre, with the prospect of realizing cheap ultra-sensitive all-in-fibre bio-sensors or absorptive polarizers.

For more highlights, refer to individual research project pages here...