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import meep as mp
import numpy as np
from meep.materials import Si, SiO2
import unittest
class TestMaterialGrid(unittest.TestCase):
def gen_sim(self):
resolution = 10 # pixels/um
cell_size = mp.Vector3(14,14)
pml_layers = [mp.PML(thickness=2)]
w = 3.0 # width of waveguide
m1 = SiO2
m2 = Si
n = 10
gs = mp.Vector3(n,n)
np.random.seed(1)
dp = np.random.rand(n*n)
mg = mp.MaterialGrid(gs,m1,m2,dp,"U_SUM")
geometry = []
rot_angle = np.radians(0)
geometry += [mp.Block(center=mp.Vector3(),
size=mp.Vector3(w,w,mp.inf),
e1=mp.Vector3(x=1).rotate(mp.Vector3(z=1), rot_angle),
e2=mp.Vector3(y=1).rotate(mp.Vector3(z=1), rot_angle),
material=mg)]
geometry += [mp.Block(center=mp.Vector3(),
size=mp.Vector3(w,w,mp.inf),
e1=mp.Vector3(x=-1).rotate(mp.Vector3(z=1), np.pi/2),
e2=mp.Vector3(y=1).rotate(mp.Vector3(z=1), np.pi/2),
material=mg)]
fsrc = 1/1.55 # frequency of eigenmode or constant-amplitude source
bnum = 1 # band number of eigenmode
kpoint = mp.Vector3(x=1).rotate(mp.Vector3(z=1), rot_angle)
compute_flux = True # compute flux (True) or plot the field profile (False)
eig_src = True # eigenmode (True) or constant-amplitude (False) source
if eig_src:
sources = [mp.EigenModeSource(src=mp.GaussianSource(fsrc,fwidth=0.2*fsrc) if compute_flux else mp.ContinuousSource(fsrc),
center=mp.Vector3(),
size=mp.Vector3(y=3*w),
direction=mp.NO_DIRECTION,
eig_kpoint=kpoint,
eig_band=bnum,
eig_parity=mp.EVEN_Y+mp.ODD_Z if rot_angle == 0 else mp.ODD_Z,
eig_match_freq=True)]
else:
sources = [mp.Source(src=mp.GaussianSource(fsrc,fwidth=0.2*fsrc) if compute_flux else mp.ContinuousSource(fsrc),
center=mp.Vector3(),
size=mp.Vector3(y=3*w),
component=mp.Ez)]
sim = mp.Simulation(cell_size=cell_size,
resolution=resolution,
boundary_layers=pml_layers,
sources=sources,
extra_materials = [m1,m2],
geometry=geometry
)
return sim
def test_eval(self):
sim = self.gen_sim()
if __name__ == '__main__':
unittest.main()
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