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
96
97
98
99
100
101
102
103
104
105
|
import meep as mp
import numpy as np
from numpy import linalg as LA
import matplotlib.pyplot as plt
n = 3.4
w = 1
r = 1
pad = 4
dpml = 2
sxy = 2*(r+w+pad+dpml)
cell_size = mp.Vector3(sxy,sxy)
pml_layers = [mp.PML(dpml)]
nonpml_vol = mp.Volume(mp.Vector3(), size=mp.Vector3(sxy-2*dpml,sxy-2*dpml))
geometry = [mp.Cylinder(radius=r+w, material=mp.Medium(index=n)),
mp.Cylinder(radius=r)]
fcen = 0.118
src = [mp.Source(mp.ContinuousSource(fcen),
component=mp.Ez,
center=mp.Vector3(r+0.1)),
mp.Source(mp.ContinuousSource(fcen),
component=mp.Ez,
center=mp.Vector3(-(r+0.1)),
amplitude=-1)]
symmetries = [mp.Mirror(mp.X,phase=-1),
mp.Mirror(mp.Y,phase=+1)]
sim = mp.Simulation(cell_size=cell_size,
geometry=geometry,
sources=src,
resolution=10,
force_complex_fields=True,
symmetries=symmetries,
boundary_layers=pml_layers)
num_tols = 5
tols = np.power(10, np.arange(-8.0,-8.0-num_tols,-1.0))
ez_dat = np.zeros((122,122,num_tols), dtype=np.complex_)
for i in range(num_tols):
sim.init_sim()
sim.solve_cw(tols[i], 10000, 10)
ez_dat[:,:,i] = sim.get_array(vol=nonpml_vol, component=mp.Ez)
err_dat = np.zeros(num_tols-1)
for i in range(num_tols-1):
err_dat[i] = LA.norm(ez_dat[:,:,i]-ez_dat[:,:,num_tols-1])
plt.figure(dpi=150)
plt.loglog(tols[:num_tols-1], err_dat, 'bo-');
plt.xlabel("frequency-domain solver tolerance");
plt.ylabel("L2 norm of error in fields");
plt.show()
eps_data = sim.get_array(vol=nonpml_vol, component=mp.Dielectric)
ez_data = np.real(ez_dat[:,:,num_tols-1])
plt.figure()
plt.imshow(eps_data.transpose(), interpolation='spline36', cmap='binary')
plt.imshow(ez_data.transpose(), interpolation='spline36', cmap='RdBu', alpha=0.9)
plt.axis('off')
plt.show()
if np.all(np.diff(err_dat) < 0):
print("PASSED solve_cw test: error in the fields is decreasing with increasing resolution")
else:
print("FAILED solve_cw test: error in the fields is NOT decreasing with increasing resolution")
sim.reset_meep()
df = 0.08
src = [mp.Source(mp.GaussianSource(fcen,fwidth=df),
component=mp.Ez,
center=mp.Vector3(r+0.1)),
mp.Source(mp.GaussianSource(fcen,fwidth=df),
component=mp.Ez,
center=mp.Vector3(-(r+0.1)),
amplitude=-1)]
sim = mp.Simulation(cell_size=mp.Vector3(sxy,sxy),
geometry=geometry,
sources=src,
resolution=10,
symmetries=symmetries,
boundary_layers=pml_layers)
dft_obj = sim.add_dft_fields([mp.Ez], fcen, 0, 1, where=nonpml_vol)
sim.run(until_after_sources=100)
eps_data = sim.get_array(vol=nonpml_vol, component=mp.Dielectric)
ez_data = np.real(sim.get_dft_array(dft_obj, mp.Ez, 0))
plt.figure()
plt.imshow(eps_data.transpose(), interpolation='spline36', cmap='binary')
plt.imshow(ez_data.transpose(), interpolation='spline36', cmap='RdBu', alpha=0.9)
plt.axis('off')
plt.show()
|
