#include "ocsOptSignal.hh"
#include "ocsOptFiberLocalError.hh"
Go to the source code of this file.
Classes | |
class | SaturableAbsorber |
Enumerations | |
enum | typeSaturableAbsorption { NO_SAT_ABS = 0, QUADRATIC_NO_LOSS_ANALYTIC = 1, QUADRATIC_NO_LOSS = 2, QUADRATIC_WITH_LOSS_ANALYTIC = 3, QUADRATIC_WITH_LOSS = 4, RATIONAL_QUADRATIC = 5, COUPLED_ODE = 6 } |
An enumeration type for the type of saturable absorber. More... |
An enumeration type for the type of saturable absorber.
Fast saturable absorber with a quadratic nonlinearity
du/dz = *(|u|^2)*u.
Solved analytically. See OptFiberLocalError class
Fast saturable absorber with a quadratic nonlinearity
du/dz = *(|u|^2)*u.
Solved numerically using Heun's method
We use parameter name:
FastSaturableAbsorptionNonlinearCoefficient =
Uses analytical formula for exact solution of fast saturable absorber with a quadratic nonlinearity and loss
Fast saturable absorber with a quadratic nonlinearity and loss, ie, du/dz = *(|u|^2 - )*u. Solved numerically using Heun's method
We use parameter names:
FastSaturableAbsorptionNonlinearCoefficient = FastSaturableAbsorptionAttenuationCoefficient =
Fast saturable absorber along lines of Ablowitz/Kaertner/Chen-Menyuk models:
du/dz = -*/(1 + |u|^2/)*u
Solved numerically using Heun's method.
The parameters were chosen so that if use 1+x 1-x approximation, then the equation agrees with QUADRATIC_WITH_LOSS.
We use parameter names:
FastSaturableAbsorptionNonlinearCoefficient = FastSaturableAbsorptionAttenuationCoefficient =
Slow saturable absorber based on Haus JQE 11 (9) Sept 1975, pp 736-746. Also see book of W. Koechner and M. Bass.
du/dz = -l(z,t)u dl/dt = - (l-l_U)/tau - l|u(z,t)|^2/(tau*P_{sat})
where l=l(z,t) is saturable loss in m^{-1} l_U is unsaturated loss in m^{-1} tau is relaxation time in seconds P_{sat} is saturation power in Watts.
For each z, we solve for l using initial condition that l(t=0)=l_U where we assume t=0 is such that u(z,0) = 0 holds, ie pulse is not centered near t=0. We run ODE solver for t forward in time.
This model is based on a three-level atomic system with a fast relaxation of the upper level. We assume that saturable absorber relaxes completely between pulses, ie, when only one pulse in laser at a time we are assuming that << Round trip time in laser.