add nonlinearity page to documentation

WUST-FOG · Sep 2, 2021 · c242f75 · c242f75
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diff --git a/README.md b/README.md
@@ -93,9 +93,12 @@ And you expect to visualise supercontinuum generation process in use of 3 types
 
 ## Release History
 
-v1.1.1 was released in 28/8/2021.
+v1.1.2 was released in 30/8/2021.
 The master branch works with **python 3.7**.
 
+* **1.1.2 -> Aug 30th, 2021**
+    * ADD: Continious wave envelope
+    * FIX: Shift scalling data for nonlinear coefficient
 * **1.1.1 -> Aug 28th, 2021**
     * CHANGE: Minor bug fix with scaling
     * CHANGE: Few minor changes in the documentation

diff --git a/docs/code_documentation.rst b/docs/code_documentation.rst
@@ -36,6 +36,21 @@ and calculated from effective refractive indices.
    gnlse.DispersionFiberFromTaylor
    gnlse.DispersionFiberFromInterpolation
 
+Nonlinear coefficient
+---------------------
+
+The guided fiber mode has a certain effective mode area, which in general
+depends on frequency. Package supports two possibilites to account
+the parameter: by giving the scalar value for gamma at central wavelength
+or calculated values for freqency range from effective refractive indices
+and effective mode area (experimantal or simulated data)
+Mode profile dispersion in GNLSE is accounted based on algorithm
+described in [J07]_.
+
+.. autosummary::
+
+   gnlse.NonlinearityFromEffectiveArea
+
 Raman responses
 ---------------
 

diff --git a/docs/dispersion.rst b/docs/dispersion.rst
@@ -3,5 +3,8 @@
 Dispersion operators
 ====================
 
-.. autoclass::DispersionFiberFromTaylor 
-.. autoclass::DispersionFiberFromInterpolation
+Package supports two dispersion operators: calculated from a Taylor expansion
+and calculated from effective refractive indices.
+
+.. autoclass:: gnlse.DispersionFiberFromTaylor 
+.. autoclass:: gnlse.DispersionFiberFromInterpolation
diff --git a/docs/gnlse_intro.rst b/docs/gnlse_intro.rst
@@ -92,6 +92,9 @@ Major features
        and temporal characteristics of a third-order soliton,
      * ``test_dispersion.py``, an example of supercontinuum generation using
        different dispersion operators,
+     * ``test_nonlinearity.py``, an example of supercontinuum generation using
+       different GNLSE and M-GNLSE
+       (take into account mode profile dispersion),  
      * ``test_Dudley``, an example of supercontinuum generation using
        different input impulse envelopes,
      * ``test_gvd``, showing impulse broadening due to group velocity
@@ -107,12 +110,14 @@ Major features
 Release information
 -------------------
 
-v1.1.1 was released on August 28, 2021. The master branch works with
+v1.1.2 was released on August 30, 2021. The master branch works with
 **Python 3.7.**
 
 =======  ===============  ====================================================
 Version  Date             Notes
 =======  ===============  ====================================================
+1.1.2    August 30, 2021  * ADD: Continious wave envelope
+                          * FIX: Shift scalling data for nonlinear coefficient
 1.1.1    August 28, 2021  * CHANGE: Minor bug fix with scaling
                           * CHANGE: Few minor changes in the documentation
 1.1.0    August 21, 2021  * Modified-GNLSE extension

diff --git a/docs/nonlinearity.rst b/docs/nonlinearity.rst
@@ -0,0 +1,30 @@
+:orphan:
+
+Nonlinear coefficient
+=====================
+
+The time derivative term inside GNLSE models the dispersion of
+the nonlinearity. This is usually assiociated with effects such
+as self-steepening and optical shock formation, characterized by
+a timescale :math:`\tau_0 = 1/\omega_0`. In the context of fibre
+propagation, additional disperison of the nonlinearity arises
+from the frequency dependence of the effective area,
+and :math:`\tau_0 = 1/\omega_0` can be generalized for this in
+an approximate manner.
+
+A better aproach is to include the dispersion of the nonlinear response is to
+describe it directly in the frequency domain [J07]_.
+In this case we can derive a GNLSE for the pulse evolution using
+:math:`\gamma(\omega)` defined as
+
+.. math::
+
+   \gamma(\omega) = \frac{n_2 n_0 \omega}{c n_{eff}( \omega ) A_{eff}^{1/4}(\omega )},
+
+with the substitution for the envelope of amplitude as scaled variable
+
+.. math::
+
+   C(z, \omega) = \frac{A_{eff}^{1/4}(\omega_0 )}{A_{eff}^{1/4}(\omega )} A(z, \omega).
+
+.. autoclass:: gnlse.NonlinearityFromEffectiveArea