# The dispersion model is built from a Taylor expansion with coefficients
# given below.
loss = 0
betas = np.array([
-0.024948815481502, 8.875391917212998e-05, -9.247462376518329e-08,
1.508210856829677e-10
])
setup.dispersion_model = gnlse.DispersionFiberFromTaylor(loss, betas)
# Input impulse parameters
power = 10000
# pulse duration [ps]
tfwhm = 0.05
# hyperbolic secant
setup.impulse_model = gnlse.SechEnvelope(power, tfwhm)
# Simulation
###########################################################################
# Type of dyspersion operator: build from Taylor expansion
setup.dispersion = gnlse.DispersionFiberFromTaylor(loss, betas)
solver = gnlse.GNLSE(setup)
solution = solver.run()
# Visualization
###########################################################################
plt.figure(figsize=(10, 8))
plt.subplot(2, 2, 1)
plt.title("Results for Taylor expansion")
gnlse.plot_wavelength_vs_distance(solution, WL_range=[400, 1400])
setup = gnlse.GNLSESetup()
# Numerical parameters
setup.resolution = 2**14
setup.time_window = 12.5 # ps
setup.z_saves = 400
# Input impulse parameters
peak_power = 10000 # W
duration = 0.050284 # ps
# Physical parameters
setup.wavelength = 835 # nm
setup.fiber_length = 0.15 # m
setup.nonlinearity = 0.11 # 1/W/m
setup.impulse_model = gnlse.SechEnvelope(peak_power, duration)
setup.self_steepening = True
# The dispersion model is built from a Taylor expansion with coefficients
# given below.
loss = 0
betas = np.array([
-11.830e-3, 8.1038e-5, -9.5205e-8, 2.0737e-10, -5.3943e-13, 1.3486e-15,
-2.5495e-18, 3.0524e-21, -1.7140e-24
])
setup.dispersion_model = gnlse.DispersionFiberFromTaylor(loss, betas)
# This example extends the original code with additional simulations for
# three types of models of Raman response and no raman scattering case
raman_models = {
'Blow-Wood': gnlse.raman_blowwood,
# The dispersion model is built from a Taylor expansion with coefficients
# given below.
loss = 0
betas = np.array([
-11.830e-3, 8.1038e-5, -9.5205e-8, 2.0737e-10, -5.3943e-13, 1.3486e-15,
-2.5495e-18, 3.0524e-21, -1.7140e-24
])
setup.dispersion_model = gnlse.DispersionFiberFromTaylor(loss, betas)
# Input pulse parameters
peak_power = 10000 # W
duration = 0.050 # ps
# This example extends the original code with additional simulations for
pulse_models = [
gnlse.SechEnvelope(peak_power, duration),
gnlse.GaussianEnvelope(peak_power, duration),
gnlse.LorentzianEnvelope(peak_power, duration)
]
count = len(pulse_models)
plt.figure(figsize=(14, 8), facecolor='w', edgecolor='k')
for i, pulse_model in enumerate(pulse_models):
print('%s...' % pulse_model.name)
setup.pulse_model = pulse_model
solver = gnlse.GNLSE(setup)
solution = solver.run()
plt.subplot(2, count, i + 1)
plt.title(pulse_model.name)
t0 = tFWHM / 2 / np.log(1 + np.sqrt(2))
# 3rd order soliton conditions
###########################################################################
# Dispersive length
LD = t0 ** 2 / np.abs(betas[0])
# Non-linear length for 3rd order soliton
LNL = LD / (3 ** 2)
# Input pulse: peak power [W]
power = 1 / (LNL * setup.nonlinearity)
# Length of soliton, in which it break dispersive characteristic
Z0 = np.pi * LD / 2
# Fiber length [m]
setup.fiber_length = .5
# Type of impulse: hyperbolic secant
setup.impulse_model = gnlse.SechEnvelope(power, 0.050)
# Loss coefficient [dB/m]
loss = 0
# Type of dyspersion operator: build from Taylor expansion
setup.dispersion_model = gnlse.DispersionFiberFromTaylor(loss, betas)
# Type of Ramman scattering function: None (default)
# Selftepening: not accounted
setup.self_steepening = False
# Simulation
###########################################################################
solver = gnlse.gnlse.GNLSE(setup)
solution = solver.run()
# Visualization
import matplotlib.pyplot as plt
import gnlse
if __name__ == '__main__':
# time full with half maximum of impulse
FWHM = 2
# Time grid [ps]
T = np.linspace(-2 * FWHM, 2 * FWHM, 1000 * FWHM)
# peak power [W]
Pmax = 100
# Amplitude envelope of gaussina impulse
A1 = gnlse.GaussianEnvelope(Pmax, FWHM).A(T)
# Amplitude envelope of hiperbolic secans impulse
A2 = gnlse.SechEnvelope(Pmax, FWHM).A(T)
# Amplitude envelope of lorentzian impulse
A3 = gnlse.LorentzianEnvelope(Pmax, FWHM).A(T)
plt.figure(figsize=(12, 8))
plt.subplot(1, 2, 1)
plt.plot(T, A1, label='gauss')
plt.plot(T, A2, label='sech')
plt.plot(T, A3, label='lorentz')
plt.xlabel("Time [ps]")
plt.ylabel("Amplitude [sqrt(W)]")
plt.legend()
plt.subplot(1, 2, 2)
plt.plot(T, A1**2, label='gauss')
plt.plot(T, A2**2, label='sech')