Fibres¶

The fiber element (single-mode fibres and waveguides: Taylor coefficients of the propagation constant, γ, Raman, loss and gain; see Fibres and waveguides) on three textbook problems whose answers are known. Each shows the evolution along the fibre as a heat map and ends with an assertion against theory.

example	the story	the number it checks
soliton-breathing	N = 1 soliton keeps its shape; N = 3 breathes and returns after z0 = (pi/2) L_D	peak power within 0.03 % (N = 1); back to 1.003 x at z0
raman-soliton-shift	Raman scattering slides a soliton to the red, faster the shorter it is	rate proportional to T0^-4 (fitted -4.3)
spm-compression	SPM broadens the spectrum in a normal-dispersion fibre, a compressor shortens the pulse	pure-SPM bandwidth growth 8.85 x = formula; 300 fs to 88 fs

Also in the repository: the Dudley PCF supercontinuum benchmark (Nonlinear/supercontinuum) and the coherence study that goes with it. Run: python docs/examples/make_all.py --group Fibres.