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import meep as mp
from meep import mpb
# Compute the bands at the X point for a quarter-wave stack Bragg
# mirror (this is the point that defines the band gap edges).
# the high and low indices:
n_lo = 1.0
n_hi = 3.0
w_hi = n_lo / (n_hi + n_lo) # a quarter_wave stack
geometry_lattice = mp.Lattice(size=mp.Vector3(1)) # 1d cell
default_material = mp.Medium(index=n_lo)
geometry = mp.Cylinder(
material=mp.Medium(index=n_hi),
center=mp.Vector3(),
axis=mp.Vector3(1),
radius=mp.inf,
height=w_hi,
)
kx = 0.5
k_points = [mp.Vector3(kx)]
resolution = 32
num_bands = 8
ms = mpb.ModeSolver(
num_bands=num_bands,
k_points=k_points,
geometry_lattice=geometry_lattice,
geometry=[geometry],
resolution=resolution,
default_material=default_material,
)
def main():
ms.run_tm(
mpb.output_hfield_y
) # note that TM and TE bands are degenerate, so we only need TM
if __name__ == "__main__":
main()
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