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
|
#!/usr/bin/env python3
# /// script
# requires-python = ">=3.10"
# dependencies = ["bornagain>=25,<26"]
# ///
"""
Specular reflectometry with sliced cylinders (Q-scan variant).
Same sample as SpecularWithSlicing2.py but the scan axis is q_z
instead of incident angle.
"""
from math import pi, sin
import numpy as np
import bornagain as ba
ba.require_versions("bornagain>=25,<26")
from bornagain import angstrom, deg, nm
HEIGHT = 5 * nm
RADIUS = 5 * nm
SURF_DENSITY = 0.01 # nm^-2
N_SLICES = 3
WAVELENGTH = 1.54 * angstrom
def _sld(delta, beta):
"""
Convert refractive index (delta, beta) to SLD (Å⁻²) at WAVELENGTH.
"""
f = pi * angstrom**2 / WAVELENGTH**2
return (2*delta - delta**2 + beta**2) * f, (2*beta - 2*delta*beta) * f
def get_sample():
vacuum = ba.Vacuum()
sub_re, sub_im = _sld(6e-6, 2e-8)
par_re, par_im = _sld(6e-4, 2e-8)
substrate_color = (0.28, 0.57, 0.82)
substrate_mat = ba.SLDMaterial("Substrate", substrate_color, sub_re, sub_im)
particle_color = (0.86, 0.24, 0.18)
particle_mat = ba.SLDMaterial("Particle", particle_color, par_re, par_im)
cylinder = ba.Cylinder(RADIUS, HEIGHT)
particle = ba.Particle(particle_mat, cylinder)
top_layer = ba.Layer(vacuum)
top_layer.deposit2D(ba.Dilute2D(SURF_DENSITY, particle))
top_layer.setNumberOfSlices(N_SLICES)
sample = ba.Sample()
sample.addLayer(top_layer)
sample.addLayer(ba.Layer(substrate_mat))
return sample
def get_simulation(sample):
n = 500
lam = WAVELENGTH
qs = [4*pi*sin(a)/lam for a in np.linspace(5*deg/n, 5*deg, n)]
scan = ba.QzScan(qs)
return ba.SpecularSimulation(scan, sample)
if __name__ == '__main__':
sample = get_sample()
ba.showSample3D(sample, sample_size=120*nm, seed=0)
simulation = get_simulation(sample)
result = simulation.simulate()
ba.plot_datafield(result)
ba.plt.show()
|
BornAgain
≻ git-develop
≻ Documentation ≻ Examples ≻ Specular ≻ Roughness and slicing ≻ Specular with slicing 2Q
