Fibre
=====

.. note::
   It is assumed that pyofss has been imported using

   >>> from pyofss import *

The fibre module may be regarded as the core of pyofss.

A default fibre may be generated using

   >>> fibre = Fibre()

For a more interesting fibre, modify the nonlinear parameter

   >>> fibre = Fibre( gamma = 1.0 )

With an input pulse with sufficient power, there should be spectral broadening

.. plot::
   :include-source:

   from pyofss import *
   sys = System()
   sys.add( Gaussian(peak_power = 10.0, width = 1.0) )
   sys.add( Fibre(gamma = 1.0) )
   sys.run()
   single_plot( sys.domain.nu, spectral_power(sys.field, True), 
                labels['nu'], labels['P_nu'] )

General dispersion may be included using the beta parameter.
For third-order dispersion pass an array with third element (including a zeroth element) non-zero

   >>> fibre = Fibre( beta = [0.0, 0.0, 0.0, 1.0] )

With an appropriate length of fibre the dispersion effects may be seen

.. plot::
   :include-source:

   from pyofss import *
   sys = System()
   sys.add( Gaussian(peak_power = 1.0, width = 1.0) )
   sys.add( Fibre(beta = [0.0, 0.0, 0.0, 1.0], length = 10.0) )
   sys.run()
   single_plot( sys.domain.t, temporal_power(sys.field), 
                labels['t'], labels['P_t'] )