Supercontinuum Generation and Related Processes                                                                            

Supercontinuum Generation

A key area of my research since 2000 has focused on studying nonlinear propagation and supercontinuum generation in highly nonlinear and photonic crystal fibers (PCF).  This work has involved experiments carried out by my own group in France, as well as analysis of results from a number of international groups.

Amongst the major results obtained include:

  • First demonstration of PCF supercontinuum generation in the
    nanosecond regime using a compact microchip laser system.
  • Detailed numerical modeling of pulse propagation and supercontinuum generation in PCF in both the nanosecond and femtosecond regimes
  • Use of the spectrogram representation to physically interpret the
    complex temporal and spectral characteristics of supercontinuum
    generation
  • Detailed numerical modeling of the stability and coherence properties of supercontinuum generation

Selected Publications

R. Trebino, J. M. Dudley, X. Gu, "Measuring and Understanding the Most Complex Ultrashort Pulse Ever Generated,"
Optics and Photonics News 14, Optics in 2003 (2003)
(PDF)

J. M. Dudley, G. Genty, S. Coen, "Supercontinuum Generation in Photonic Crystal Fiber,"
Reviews of Modern Physics 78 1135-1184 (2006)
(PDF)

Notes on Simulation and Modelling

Modelling ultrabroadband propagation is often assumed to be limited by "slowly varying" approximations.  However it's a little more subtle than it seems, and the key approximation is one that assumes unidirectional approximation.  A well constructed "envelope" equation can in fact yield results in agreement with Maxwell's equations over bandwidths that are many multiples of the carrier frequency.  The 2007 paper by Genty et al. listed below gives an explicit demonstration of this, but in fact the idea goes back many years and many of the references in this paper explain the details very cleary. 

Another effect that needs to be taken into account is the fact that different wavelengths in a supercontinuum propagate in modes with different effective areas.  Including the frequency dependence of the effective area in nonlinear propagation equations reveals a decrease in the effective nonlinearity experienced by longer wavelengths.  This is crucial for quantitative agreement with experiment.

Selected Publications

B. Kibler, J. M. Dudley, S. Coen, "Supercontinuum generation and nonlinear pulse propagation in photonic crystal fiber: influence of the frequency-dependent effective mode area," Appl. Phys. B 81 337-342 (2005) (LINK)

G. Genty, P. Kinsler, B. Kibler, J. M. Dudley, "Nonlinear envelope equation modeling of sub-cycle dynamics and harmonic generation in nonlinear waveguides," 
Opt. Express 15, 5382-5387 (2007) (PDF)

Ultrafast optical self-similarity

A related research topic since 2000 has been the study of the generation and propagation of self-similar pulses in optical amplifiers known as similaritons (a term introduced by myself and John Harvey from the University of Auckland).

This is an area of research of intense current interest, with many groups exploiting the self-similar propagation dynamics to scale optical fiber amplifiers to higher power.  My own research has concentrated on studying the more fundamental aspects of the underlying self-similar pulse propagation dynamics. Amongst the results obtained include the demonstration of a Raman-based similariton amplifier, the direct experimental demonstration of the asymptotic nature of the output similariton pulses, and the use of high dynamic range FROG to directly confirm the self-similar nature of pulse propagation in the similariton regime.

These results have recently been extended to the full spatio-temporal case as well.  

Selected Publications

J. M. Dudley, C. Finot, D. J. Richardson, G, Millot, "Self Similarity in Ultrafast Nonlinear Optics," Nature Physics 3 597-603 (2007). 
The final formatted PDF must be obtained from the Nature website but an early preprint version is available here (PDF).

Spatiotemporal nonlinear optical self-similarity in three dimensions
Physical Review Letters 102 233903 (2009)  (PDF)

Resources

Spectrogram Movies from Reviews of Modern Physics article (ZIP)

 

More insight 

A decade of progress has been reviewed in J. M. Dudley and J. R. Taylor, "Ten years of nonlinear optics in photonic crystal fibre," Nature Photonics 3, 85-90 (2009) (LINK)

Extreme value instabilities are analysed in J. M. Dudley, G. Genty, and B. J. Eggleton, "Harnessing and control of optical rogue waves in supercontinuum generation," Opt. Express 16, 3644-3651 (2008) (PDF)

Soliton-dispersive wave trapping is analysed by Gorbach & Skryabin in a 2007 Nature Photonics paper  (LINK).  See also the related N&V by  Frosz and Andersen (LINK)

Soliton tunnelling effects with multiple ZDWs are analysed numerically by ourselves in Electronics Letters (LINK) and more comprehensively by Tsoy & De Sterke in PRA (LINK), both published in 2007

 

Useful Websites

G. P. Agrawal's site at the Institute of Optics at Rochester : LINK

Photonic & Sonic Band-Gap and Metamaterial Bibliography on Jonathan Dowling's site : LINK 

University of Bath Centre for Photonics and Photonic Materials :LINK

Max Planck Research Group on Photonics and New Materials in Erlangen : LINK