FreeCarrier2D
-------------

.. xml:tag:: <gain solver="FreeCarrier2D"> [FreeCarrier2D]

   Corresponding Python class: :py:class:`gain.freecarrier.FreeCarrier2D`.

   Quantum-well gain using free-carrier approximation for two-dimensional Cartesian geometry.

   This solver does not use any mesh by default and the the full gain calculation is performed in each requested point. However, if there is a mesh specified then the gain is computed only in the mesh points and interpolated in-between.

   :attr required name: Solver name.

   .. xml:contents::

      .. xml:tag:: <geometry> [in gain.FreeCarrier2D]

         Geometry for use by this solver.

         :attr required ref: Name of a Cartesian2D geometry defined in the :xml:tag:`<geometry>` section.

      .. xml:tag:: <mesh> [in gain.FreeCarrier2D]

         Optional Ordered, Regular mesh used by this solver.

         :attr required ref: Name of a Ordered, Regular mesh defined in the :xml:tag:`<grids>` section.

      .. xml:tag:: <config> [in gain.FreeCarrier2D]

         Some important gain parameters.

         :attr lifetime: Average carriers lifetime. This parameter is used for gain spectrum broadening. (float (ps), default 0.1 ps)
         :attr matrix-elem: Value of the squared matrix element in gain computations. If it is not set it is estimated automatically. (float (eV×m\ :sub:`0`\ ))
         :attr strained: Boolean attribute indicating if the solver should consider strain in the active region. If set to \ *yes*\  then the substrate material must be either explicitly specified of there must a layer with the role "\ *substrate*\ " in the geometry. The strain is computed by comparing the atomic lattice constants of the substrate and the quantum wells. (bool, default is \ ``no``\ )
         :attr substrate: Name of the substrate material. This attribute is used only if the \ *strained*\  attribute is set to \ *yes*\ . If this attribute is not set then the substrate material must be specified by a layer with the role "\ *substrate*\ ". (material)
         :attr T0: Reference temperature. This is the temperature used for initial computation of the energy levels. (float (K), default 300 K)
