Publications by the Laboratory of Theoretical Physics

Tunable narrow-band spectral peak imposed onto a   soliton with an acoustic long-period grating, J. A. Bolger , F. Luan, Dong-Il Yeom, E. N. Tsoy, C. M. de Sterke,  B. J. Eggleton, Proc. of the SPIE, 6801,  p. 68010B (2008).    [PDF-file  (326 kB)] Abstract: We demonstrate a method of local spectral enhancement of an ultrafast soliton pulse. We use an in-line acoustic long-period grating (LPG), a periodic structure modifying both the phase and the loss of the propagating light, and which is readily tuned by simple adjustment of an applied electrical signal. The soliton perturbed by this narrow-band filter evolves with nonlinear propagation into an intense localised spectral peak. Our setup consists of creation of a red-shifted optical soliton by propagation of pulses from a fibre laser in standard single-mode optical fibre, followed by imposition of a spectrally narrow LPG near to the soliton peak, and then continuing propagation. The wavelength and the peak value of the resulting local enhancement can be tuned by adjustment of the applied acoustic frequency and amplitude. The physics of the observed local spectral enhancement will be discussed in detail here. The papers have Copyright © by the corresponding publishers. The papers may be downloaded for personal use only. Any other use requires prior permission of the author and the publisher.