from pynlo.light.DerivedPulses import CWPulse
from pynlo.media import crystals
from pynlo.interactions.ThreeWaveMixing import dfg_problem
from pynlo.util import ode_solve
from pynlo.util.ode_solve import dopr853
from mpl_toolkits.axes_grid1.inset_locator import inset_axes
plt.close('all')
# Test pump depetion in case where pump & signal photon counts are the same.
# Idea from Brian Washburn
npoints = 2**6
# Physical lengths are in meters
crystallength = 0.10
crystal = crystals.AgGaSe2()
n_saves = 1000
# Wavelengths are in nanometers
pump_wl_nm = 1560.
sgnl_wl_nm = 2200.
theta, idlr_wl_nm = crystal.phasematch(pump_wl_nm, sgnl_wl_nm, None, return_wavelength = True)
crystal.set_theta(theta)
pump_power = 2500000.0
sgnl_power = pump_power*sgnl_wl_nm / pump_wl_nm
idlr_power = 0.000
def test_fn(self):
npoints = 2**6
# Physical lengths are in meters
crystallength = 0.010
crystal = crystals.AgGaSe2()
crystal = crystals.AgGaSe2(length=crystallength)
n_saves = 10
# Wavelengths are in nanometers
pump_wl_nm = 1560. + 10.0 * np.random.rand()
sgnl_wl_nm = 2200. + 10.0 * np.random.rand()
theta, idlr_wl_nm = crystal.phasematch(pump_wl_nm,
sgnl_wl_nm,
None,
return_wavelength=True)
crystal.set_theta(theta)
pump_power = (1 + np.random.rand()) * 5000.0
sgnl_power = 0.10 * np.random.rand()
twind = 25.
beamwaist = 100e-3
pump_in = CWPulse(pump_power,
pump_wl_nm,
NPTS=npoints,
time_window_ps=twind)
sgnl_in = CWPulse(sgnl_power,
sgnl_wl_nm,
NPTS=npoints,
time_window_ps=twind)
integrand = dfg_problem(pump_in,
sgnl_in,
crystal,
disable_SPM=True,
pump_waist=beamwaist,
apply_gouy_phase=True)
# Set up integrator
rtol = 1.0e-12
atol = 1.0e-12
x0 = 0.0
x1 = crystallength
hmin = 0.0
h1 = 0.0000001
out = ode_solve.Output(n_saves)
# From Boyd section 2.8, also my One Note
omega = lambda l_nm: 2.0 * np.pi * speed_of_light / (l_nm * 1.0e-9)
w_1 = omega(sgnl_wl_nm)
w_2 = omega(idlr_wl_nm)
k_1 = np.mean(2 * np.pi * crystal.n(sgnl_wl_nm, 'o') /
(sgnl_wl_nm * 1.0e-9))
k_2 = np.mean(2 * np.pi * crystal.n(idlr_wl_nm, 'o') /
(idlr_wl_nm * 1.0e-9))
n_1 = crystal.n(sgnl_wl_nm, 'o')
n_2 = crystal.n(idlr_wl_nm, 'o')
n_3 = crystal.n(pump_wl_nm, 'mix')
A_3 = np.sqrt(pump_power) * integrand.pump_beam.rtP_to_a(
crystal.n(pump_wl_nm, 'mix'))
A_1 = np.sqrt(sgnl_power) * integrand.sgnl_beam.rtP_to_a(
crystal.n(sgnl_wl_nm, 'o'))
kappa = np.mean(
np.sqrt(4 * crystal.deff**2 * w_1**2 * w_2**2 /
(k_1 * k_2 * speed_of_light**4)) * A_3)
a = ode_solve.ODEint(integrand.ystart, x0, x1, atol, rtol, h1,hmin, out,\
dopr853.StepperDopr853, integrand, dtype = np.complex128)
a.integrate()
pump_out = a.out.ysave[0:a.out.count, 0:npoints].T
sgnl_out = a.out.ysave[0:a.out.count, npoints:2 * npoints].T
idlr_out = a.out.ysave[0:a.out.count, 2 * npoints:3 * npoints].T
z = a.out.xsave[0:a.out.count]
pump_power_in = np.sum(np.abs(pump_out[:, 0]), axis=0)**2
sgnl_power_in = np.sum(np.abs(sgnl_out[:, ])**2, axis=0)
idlr_power_in = np.sum(np.abs(idlr_out[:, 0]), axis=0)**2
pump_power_out = np.sum(np.abs(pump_out[:, -1]))**2
sgnl_power_out = np.sum(np.abs(sgnl_out[:, -1]))**2
idlr_power_out = np.sum(np.abs(idlr_out[:, -1]))**2
# Compare integrated and analytic values for signal power
numeric_sgnl = np.sum(np.abs(sgnl_out[:, :])**2, axis=0)
analytic_sgnl = sgnl_power_in * np.cosh(kappa * z)**2
self.assertLess(
abs(
np.sum(numeric_sgnl - analytic_sgnl) /
np.sum(abs(analytic_sgnl))), 0.01)
# Compare integrated and analytic values for idler power
numeric_idlr = np.sum(np.abs(idlr_out[:, :])**2, axis=0)
analytic_idlr = n_1 * w_2 / (n_2 * w_1) * sgnl_power_in * np.sinh(
kappa * z)**2
self.assertLess(
abs(
np.sum(numeric_idlr - analytic_idlr) /
np.sum(abs(analytic_idlr))), 0.02)