1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
|
"""
Resonator in off-specular experiment.
"""
import bornagain as ba
from bornagain import deg, nm, micrometer, angstrom
def get_sample(nlayers=3):
"""
Construct resonator with given number of Ti/Pt double layers nlayers.
"""
# define materials
m_Si = ba.HomogeneousMaterial("Si", 8.25218379931e-06, 0.0)
m_Ti = ba.HomogeneousMaterial("Ti", -7.6593316363e-06, 3.81961616312e-09)
m_TiO2 = ba.HomogeneousMaterial("TiO2", 1.04803530026e-05,
2.03233519385e-09)
m_Pt = ba.HomogeneousMaterial("Pt", 2.52936993309e-05, 7.54553992473e-09)
m_D2O = ba.HomogeneousMaterial("D2O", 2.52897204573e-05, 4.5224432814e-13)
# create layers
l_TiO2 = ba.Layer(m_TiO2, 3.0*nm)
l_Ti_top = ba.Layer(m_Ti, 10.0*nm)
l_Ti = ba.Layer(m_Ti, 13.0*nm)
l_Si = ba.Layer(m_Si) # consider it as an ambient layer
l_Pt = ba.Layer(m_Pt, 32.0*nm)
l_D2O = ba.Layer(
m_D2O) # thickness is not given, seems to be like a substrate
# describe layer roughness
roughness = ba.LayerRoughness()
roughness.setSigma(2.0*nm)
roughness.setHurstParameter(0.8)
roughness.setLatteralCorrLength(10.0*micrometer)
# assemble multilayer
sample = ba.MultiLayer()
sample.addLayer(l_Si) # Assume huge Si block to be infinite
for i in range(nlayers):
sample.addLayerWithTopRoughness(l_Ti, roughness)
sample.addLayerWithTopRoughness(l_Pt, roughness)
sample.addLayerWithTopRoughness(l_Ti_top, roughness)
sample.addLayerWithTopRoughness(l_TiO2, roughness)
sample.addLayerWithTopRoughness(l_D2O, roughness)
sample.setCrossCorrLength(400*nm)
return sample
def get_simulation(sample):
"""
characterizing the input beam and output detector
"""
# create OffSpecular simulation
simulation = ba.OffSpecularSimulation()
if not "__no_terminal__" in globals():
simulation.setTerminalProgressMonitor()
# define detector parameters
n_alpha, alpha_min, alpha_max = 300, 0.0*deg, 4.0*deg
n_phi, phi_min, phi_max = 10, -0.1*deg, 0.1*deg
simulation.setDetectorParameters(n_phi, phi_min, phi_max, n_alpha,
alpha_min, alpha_max)
# define the beam with alpha_i varied between alpha_i_min and alpha_i_max
n_scan_points, alpha_i_min, alpha_i_max = n_alpha, alpha_min, alpha_max
alpha_i_axis = ba.FixedBinAxis("alpha_i", n_scan_points, alpha_i_min,
alpha_i_max)
simulation.setBeamParameters(5.0*angstrom, alpha_i_axis, 0.0)
simulation.beam().setIntensity(1e9)
simulation.getOptions().setIncludeSpecular(True)
# define detector resolution function with smearing depending on bin size
d_alpha = (alpha_max - alpha_min)/n_alpha
d_phi = (phi_max - phi_min)/n_phi
sigma_factor = 1.0
simulation.setDetectorResolutionFunction(
ba.ResolutionFunction2DGaussian(sigma_factor*d_alpha,
sigma_factor*d_phi))
simulation.setSample(sample)
return simulation
if __name__ == '__main__':
import ba_plot
sample = get_sample(nlayers=3)
simulation = get_simulation(sample)
ba_plot.run_and_plot(simulation, intensity_min=1e-03)
|
