Ybranch
Ybranch
Y branch
splitter and combiner
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# importing necessary packages
import gplugins.modes as gmode
import numpy as np
import matplotlib.pyplot as plt
import meep as mp
import gdsfactory as gf
import gplugins.gmeep as gm
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Using MPI version 4.1, 1 processes
[32m2025-10-02 17:22:26.906[0m | [1mINFO [0m | [36mgplugins.gmeep[0m:[36m<module>[0m:[36m39[0m - [1mMeep '1.31.0' installed at ['/home/ramprakash/anaconda3/envs/si_photo/lib/python3.13/site-packages/meep'][0m
Y-branch from gdsfactory
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gf.clear_cache()
ybranch = gf.Component("ybranch")
inwg = gf.components.straight(length=5)
outwg = gf.components.straight(length=2)
splitter = gf.components.mmi1x2_with_sbend()
inwg_ref = ybranch.add_ref(inwg)
splitter_ref = ybranch.add_ref(splitter)
outwg_top_ref = ybranch.add_ref(outwg)
outwg_bot_ref = ybranch.add_ref(outwg)
# Connecting ports
inwg_ref.connect("o2", splitter_ref.ports["o1"])
outwg_top_ref.connect("o1", splitter_ref.ports["o2"])
outwg_bot_ref.connect("o1", splitter_ref.ports["o3"])
# adding port name
ybranch.add_port(name=f"o1", port=inwg_ref.ports["o1"])
ybranch.add_port(name=f"o2", port=outwg_top_ref.ports["o2"])
ybranch.add_port(name=f"o3", port=outwg_bot_ref.ports["o2"])
ybranch.auto_rename_ports()
# plotting
ybranch.draw_ports()
ybranch.plot()
Meep simulation
S-parameter calculation and steady-state fields
50-50 splitter
Input port 1, will not be exact 50-50 because of the losses at the split
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from gdsfactory.technology import LayerLevel, LayerStack
mp.verbosity(0)
# Set up frequency points for simulation
npoints = 100
lcen = 1.55
dlam = 0.02
wl = np.linspace(lcen - dlam / 2, lcen + dlam / 2, npoints)
fcen = 1 / lcen
fwidth = 3 * dlam / lcen**2
fpoints = 1 / wl # Center frequency
mode_parity = mp.EVEN_Y + mp.ODD_Z
dpml = 1
dpad = 1
resolution = 20
# Define materials
Si = mp.Medium(index=3.45)
SiO2 = mp.Medium(index=1.45)
cell_size = mp.Vector3(ybranch.xsize + 2 * dpml, ybranch.ysize + 2 * dpml + 2 * dpad, 0)
ybranch = gf.components.extend_ports(ybranch, port_names=["o1", "o2", "o3"], length=1)
ybranch = ybranch.copy()
ybranch.flatten()
ybranch.center = (0, 0)
geometry = gm.get_meep_geometry.get_meep_geometry_from_component(ybranch)
geometry = [
mp.Prism(geom.vertices, geom.height, geom.axis, geom.center, material=Si)
for geom in geometry
]
src = mp.GaussianSource(frequency=fcen, fwidth=fwidth)
source = [
mp.EigenModeSource(
src=src,
eig_band=1,
eig_parity=mode_parity,
size=mp.Vector3(0, 1),
center=mp.Vector3(ybranch.ports["o1"].x + dpml + 1, ybranch["o1"].y),
)
]
sim = mp.Simulation(
resolution=resolution,
cell_size=cell_size,
boundary_layers=[
mp.PML(dpml)
], # the boundary layers to absorb fields that leave the simulation
sources=source, # The sources
geometry=geometry, # The geometry
default_material=SiO2,
)
m1 = mp.Volume(
center=mp.Vector3(ybranch.ports["o1"].x + dpml + 1 + 0.5, ybranch["o1"].y),
size=mp.Vector3(0, 1),
)
m2 = mp.Volume(
center=mp.Vector3(ybranch.ports["o2"].x - dpml - 1 - 0.5, ybranch["o2"].y),
size=mp.Vector3(0, 1),
)
m3 = mp.Volume(
center=mp.Vector3(ybranch.ports["o3"].x - dpml - 1 - 0.5, ybranch["o3"].y),
size=mp.Vector3(0, 1),
)
mode_monitor_1 = sim.add_mode_monitor(fpoints, mp.ModeRegion(volume=m1))
mode_monitor_2 = sim.add_mode_monitor(fpoints, mp.ModeRegion(volume=m2))
mode_monitor_3 = sim.add_mode_monitor(fpoints, mp.ModeRegion(volume=m3))
whole_dft = sim.add_dft_fields([mp.Ez], fcen, 0, 1, center=mp.Vector3(), size=cell_size)
sim.plot2D(labels=False)
sim.run(until_after_sources=mp.stop_when_dft_decayed(tol=1e-4))
# Finds the S parameters
norm_mode_coeff = sim.get_eigenmode_coefficients(
mode_monitor_1, [1], eig_parity=mode_parity
).alpha[0, :, 0]
port1_coeff = (
sim.get_eigenmode_coefficients(mode_monitor_1, [1], eig_parity=mode_parity).alpha[
0, :, 1
]
/ norm_mode_coeff
)
port2_coeff = (
sim.get_eigenmode_coefficients(mode_monitor_2, [1], eig_parity=mode_parity).alpha[
0, :, 0
]
/ norm_mode_coeff
)
port3_coeff = (
sim.get_eigenmode_coefficients(mode_monitor_3, [1], eig_parity=mode_parity).alpha[
0, :, 0
]
/ norm_mode_coeff
)
# Calculates the transmittance based off of the S parameters
port1_trans = abs(port1_coeff) ** 2
port2_trans = abs(port2_coeff) ** 2
port3_trans = abs(port3_coeff) ** 2
insertion_loss_dB = 10*np.log10(port2_trans)
fig = plt.figure(figsize=(15, 4))
ax_loss = fig.add_subplot(1,2,1)
ax_loss.set_title("Insertion Loss P2")
ax_loss.plot(wl,insertion_loss_dB)
ax_loss.set_xlabel(r"Wavelength (\mu m)")
ax_loss.set_ylabel("Loss (dB)")
# ax_trans1 = fig.add_subplot(1, 3, 1)
# ax_trans1.set_title("Transmission per Port")
# ax_trans1.plot(wl, port1_trans, label=r"s11^2")
# ax_trans1.plot(wl, port2_trans, label=r"s21^2")
# ax_trans1.plot(wl, port3_trans, label=r"s31^2")
# ax_trans1.set_xlabel(r"Wavelength (\mu m)")
# ax_trans1.set_ylabel(r"Transmission")
# ax_trans1.legend()
# ax_phase1 = fig.add_subplot(1, 3, 2)
# ax_phase1.set_title("Phase per Port")
# ax_phase1.plot(
# wl, np.unwrap(np.angle(port1_coeff) * 180 / np.pi), label=r"phase of s11"
# )
# ax_phase1.plot(
# wl, np.unwrap(np.angle(port2_coeff) * 180 / np.pi), label=r"phase of s21"
# )
# ax_phase1.plot(
# wl, np.unwrap(np.angle(port3_coeff) * 180 / np.pi), label=r"phase of s31"
# )
# ax_phase1.set_xlabel(r"Wavelength (\mu m)")
# ax_phase1.set_ylabel("Angle (deg)")
# ax_phase1.legend()
# sim.reset_meep()
# sim.run(until_after_sources=mp.stop_when_dft_decayed(tol=1e-4))
eps_data = sim.get_epsilon() #
ez_data = sim.get_dft_array(
whole_dft, mp.Ez, 0
) # Values for the component of the E-field in the z direction (in/out of screen)
# Creates the plot
ax_field = fig.add_subplot(1, 2, 2)
ax_field.set_title("Steady State Fields")
ax_field.imshow(np.transpose(eps_data), interpolation="spline36", cmap="binary")
ax_field.imshow(
np.flipud(np.transpose(np.real(ez_data))),
interpolation="spline36",
cmap="RdBu",
alpha=0.9,
)
ax_field.axis("off")
plt.show()
Input in single guide
Splitter
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from gdsfactory.technology import LayerLevel, LayerStack
mp.verbosity(0)
# Set up frequency points for simulation
npoints = 100
lcen = 1.55
dlam = 0.02
wl = np.linspace(lcen - dlam / 2, lcen + dlam / 2, npoints)
fcen = 1 / lcen
fwidth = 3 * dlam / lcen**2
fpoints = 1 / wl # Center frequency
mode_parity = mp.EVEN_Y + mp.ODD_Z
dpml = 1
dpad = 1
resolution = 20
# Define materials
Si = mp.Medium(index=3.45)
SiO2 = mp.Medium(index=1.45)
cell_size = mp.Vector3(ybranch.xsize + 2 * dpml, ybranch.ysize + 2 * dpml + 2 * dpad, 0)
ybranch = gf.components.extend_ports(ybranch, port_names=["o1", "o2", "o3"], length=1)
ybranch = ybranch.copy()
ybranch.flatten()
ybranch.center = (0, 0)
geometry = gm.get_meep_geometry.get_meep_geometry_from_component(ybranch)
geometry = [
mp.Prism(geom.vertices, geom.height, geom.axis, geom.center, material=Si)
for geom in geometry
]
src = mp.GaussianSource(frequency=fcen, fwidth=fwidth)
source = [
mp.EigenModeSource(
src=src,
eig_band=1,
eig_parity=mode_parity,
eig_kpoint = mp.Vector3(-1,0,0),
direction = mp.NO_DIRECTION,
size=mp.Vector3(0, 1),
center=mp.Vector3(ybranch.ports["o2"].x - dpml - 1, ybranch["o2"].y),
amplitude=1
),
# mp.EigenModeSource(
# src=src,
# eig_band=1,
# eig_parity=mode_parity,
# eig_kpoint = mp.Vector3(-1,0,0),
# direction = mp.NO_DIRECTION,
# size=mp.Vector3(0, 1),
# center=mp.Vector3(ybranch.ports["o3"].x - dpml - 1, ybranch["o3"].y),
# amplitude=1
# ),
]
sim = mp.Simulation(
resolution=resolution,
cell_size=cell_size,
boundary_layers=[mp.PML(dpml)], #
sources=source, # The sources
geometry=geometry, # The geometry
default_material=SiO2,
)
m1 = mp.Volume(
center=mp.Vector3(ybranch.ports["o1"].x + dpml + 1 + 0.5, ybranch["o1"].y),
size=mp.Vector3(0, 1),
)
m2 = mp.Volume(
center=mp.Vector3(ybranch.ports["o2"].x - dpml - 1 - 0.5, ybranch["o2"].y),
size=mp.Vector3(0, 1),
)
m3 = mp.Volume(
center=mp.Vector3(ybranch.ports["o3"].x - dpml - 1 - 0.5, ybranch["o3"].y),
size=mp.Vector3(0, 1),
)
mode_monitor_1 = sim.add_mode_monitor(fpoints, mp.ModeRegion(volume=m1))
mode_monitor_2 = sim.add_mode_monitor(fpoints, mp.ModeRegion(volume=m2))
mode_monitor_3 = sim.add_mode_monitor(fpoints, mp.ModeRegion(volume=m3))
whole_dft = sim.add_dft_fields([mp.Ez], fcen, 0, 1, center=mp.Vector3(), size=cell_size)
sim.plot2D(labels=False)
sim.run(until_after_sources=mp.stop_when_dft_decayed(tol=1e-4))
# Finds the S parameters
norm_mode_coeff = sim.get_eigenmode_coefficients(
mode_monitor_2, [1], eig_parity=mode_parity
).alpha[0, :, 1] # Adding both the ports input values
port1_coeff = (
sim.get_eigenmode_coefficients(mode_monitor_1, [1], eig_parity=mode_parity).alpha[
0, :, 1
]
/ norm_mode_coeff
)
port2_coeff = (
sim.get_eigenmode_coefficients(mode_monitor_2, [1], eig_parity=mode_parity).alpha[
0, :, 0
]
/ norm_mode_coeff
)
port3_coeff = (
sim.get_eigenmode_coefficients(mode_monitor_3, [1], eig_parity=mode_parity).alpha[
0, :, 0
]
/ norm_mode_coeff
)
# Calculates the transmittance based off of the S parameters
port1_trans = abs(port1_coeff) ** 2
port2_trans = abs(port2_coeff) ** 2
port3_trans = abs(port3_coeff) ** 2
insertion_loss_dB = 10*np.log10(port1_trans)
fig = plt.figure(figsize=(15, 4))
ax_loss = fig.add_subplot(1,2,1)
ax_loss.set_title("Insertion Loss P1")
ax_loss.plot(wl,insertion_loss_dB)
ax_loss.set_xlabel(r"Wavelength (\mu m)")
ax_loss.set_ylabel("Loss (dB)")
# ax_trans1 = fig.add_subplot(1, 3, 1)
# ax_trans1.set_title("Transmission per Port")
# ax_trans1.plot(wl, port1_trans, label=r"s1(23)^2") # Not the proper way to represent
# ax_trans1.plot(wl, port2_trans, label=r"s22^2")
# ax_trans1.plot(wl, port3_trans, label=r"s33^2")
# ax_trans1.set_xlabel(r"Wavelength (\mu m)")
# ax_trans1.set_ylabel(r"Transmission")
# ax_trans1.legend()
# ax_phase1 = fig.add_subplot(1, 3, 2)
# ax_phase1.set_title("Phase per Port")
# ax_phase1.plot(
# wl, np.unwrap(np.angle(port1_coeff) * 180 / np.pi), label=r"phase of s1(23)"
# )
# ax_phase1.plot(
# wl, np.unwrap(np.angle(port2_coeff) * 180 / np.pi), label=r"phase of s22"
# )
# ax_phase1.plot(
# wl, np.unwrap(np.angle(port3_coeff) * 180 / np.pi), label=r"phase of s33"
# )
# ax_phase1.set_xlabel(r"Wavelength (\mu m)")
# ax_phase1.set_ylabel("Angle (deg)")
# ax_phase1.legend()
# sim.reset_meep()
# sim.run(until_after_sources=mp.stop_when_dft_decayed(tol=1e-4))
eps_data = sim.get_epsilon() #
ez_data = sim.get_dft_array(
whole_dft, mp.Ez, 0
) # Values for the component of the E-field in the z direction (in/out of screen)
# Creates the plot
ax_field = fig.add_subplot(1, 2, 2)
ax_field.set_title("Steady State Fields")
ax_field.imshow(np.transpose(eps_data), interpolation="spline36", cmap="binary")
ax_field.imshow(
np.flipud(np.transpose(np.real(ez_data))),
interpolation="spline36",
cmap="RdBu",
alpha=0.9,
)
ax_field.axis("off")
plt.show()
Combiner
Out-phase
distructive interference
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from gdsfactory.technology import LayerLevel, LayerStack
mp.verbosity(0)
# Set up frequency points for simulation
npoints = 100
lcen = 1.55
dlam = 0.02
wl = np.linspace(lcen - dlam / 2, lcen + dlam / 2, npoints)
fcen = 1 / lcen
fwidth = 3 * dlam / lcen**2
fpoints = 1 / wl # Center frequency
mode_parity = mp.EVEN_Y + mp.ODD_Z
dpml = 1
dpad = 1
resolution = 20
# Define materials
Si = mp.Medium(index=3.45)
SiO2 = mp.Medium(index=1.45)
cell_size = mp.Vector3(ybranch.xsize + 2 * dpml, ybranch.ysize + 2 * dpml + 2 * dpad, 0)
ybranch = gf.components.extend_ports(ybranch, port_names=["o1", "o2", "o3"], length=1)
ybranch = ybranch.copy()
ybranch.flatten()
ybranch.center = (0, 0)
geometry = gm.get_meep_geometry.get_meep_geometry_from_component(ybranch)
geometry = [
mp.Prism(geom.vertices, geom.height, geom.axis, geom.center, material=Si)
for geom in geometry
]
src = mp.GaussianSource(frequency=fcen, fwidth=fwidth)
source = [
mp.EigenModeSource(
src=src,
eig_band=1,
eig_parity=mode_parity,
eig_kpoint = mp.Vector3(-1,0,0),
direction = mp.NO_DIRECTION,
size=mp.Vector3(0, 1),
center=mp.Vector3(ybranch.ports["o2"].x - dpml - 1, ybranch["o2"].y),
amplitude=1
),
mp.EigenModeSource(
src=src,
eig_band=1,
eig_parity=mode_parity,
eig_kpoint = mp.Vector3(-1,0,0),
direction = mp.NO_DIRECTION,
size=mp.Vector3(0, 1),
center=mp.Vector3(ybranch.ports["o3"].x - dpml - 1, ybranch["o3"].y),
amplitude=-1
),
]
sim = mp.Simulation(
resolution=resolution,
cell_size=cell_size,
boundary_layers=[mp.PML(dpml)], #
sources=source, # The sources
geometry=geometry, # The geometry
default_material=SiO2,
)
m1 = mp.Volume(
center=mp.Vector3(ybranch.ports["o1"].x + dpml + 1 + 0.5, ybranch["o1"].y),
size=mp.Vector3(0, 1),
)
m2 = mp.Volume(
center=mp.Vector3(ybranch.ports["o2"].x - dpml - 1 - 0.5, ybranch["o2"].y),
size=mp.Vector3(0, 1),
)
m3 = mp.Volume(
center=mp.Vector3(ybranch.ports["o3"].x - dpml - 1 - 0.5, ybranch["o3"].y),
size=mp.Vector3(0, 1),
)
mode_monitor_1 = sim.add_mode_monitor(fpoints, mp.ModeRegion(volume=m1))
mode_monitor_2 = sim.add_mode_monitor(fpoints, mp.ModeRegion(volume=m2))
mode_monitor_3 = sim.add_mode_monitor(fpoints, mp.ModeRegion(volume=m3))
whole_dft = sim.add_dft_fields([mp.Ez], fcen, 0, 1, center=mp.Vector3(), size=cell_size)
sim.plot2D(labels=False)
sim.run(until_after_sources=mp.stop_when_dft_decayed(tol=1e-4))
# Finds the S parameters
norm_mode_coeff = sim.get_eigenmode_coefficients(
mode_monitor_2, [1], eig_parity=mode_parity
).alpha[0, :, 1] + sim.get_eigenmode_coefficients(
mode_monitor_3, [1], eig_parity=mode_parity
).alpha[0, :, 1] # Adding both the ports input values
port1_coeff = (
sim.get_eigenmode_coefficients(mode_monitor_1, [1], eig_parity=mode_parity).alpha[
0, :, 1
]
/ norm_mode_coeff
)
port2_coeff = (
sim.get_eigenmode_coefficients(mode_monitor_2, [1], eig_parity=mode_parity).alpha[
0, :, 0
]
/ norm_mode_coeff
)
port3_coeff = (
sim.get_eigenmode_coefficients(mode_monitor_3, [1], eig_parity=mode_parity).alpha[
0, :, 0
]
/ norm_mode_coeff
)
# Calculates the transmittance based off of the S parameters
port1_trans = abs(port1_coeff) ** 2
port2_trans = abs(port2_coeff) ** 2
port3_trans = abs(port3_coeff) ** 2
insertion_loss_dB = 10*np.log10(port1_trans)
fig = plt.figure(figsize=(15, 4))
ax_loss = fig.add_subplot(1,2,1)
ax_loss.set_title("Insertion Loss P1")
ax_loss.plot(wl,insertion_loss_dB)
ax_loss.set_xlabel(r"Wavelength (\mu m)")
ax_loss.set_ylabel("Loss (dB)")
# ax_trans1 = fig.add_subplot(1, 3, 1)
# ax_trans1.set_title("Transmission per Port")
# ax_trans1.plot(wl, port1_trans, label=r"s1(23)^2") # Not the proper way to represent
# ax_trans1.plot(wl, port2_trans, label=r"s22^2")
# ax_trans1.plot(wl, port3_trans, label=r"s33^2")
# ax_trans1.set_xlabel(r"Wavelength (\mu m)")
# ax_trans1.set_ylabel(r"Transmission")
# ax_trans1.legend()
# ax_phase1 = fig.add_subplot(1, 3, 2)
# ax_phase1.set_title("Phase per Port")
# ax_phase1.plot(
# wl, np.unwrap(np.angle(port1_coeff) * 180 / np.pi), label=r"phase of s1(23)"
# )
# ax_phase1.plot(
# wl, np.unwrap(np.angle(port2_coeff) * 180 / np.pi), label=r"phase of s22"
# )
# ax_phase1.plot(
# wl, np.unwrap(np.angle(port3_coeff) * 180 / np.pi), label=r"phase of s33"
# )
# ax_phase1.set_xlabel(r"Wavelength (\mu m)")
# ax_phase1.set_ylabel("Angle (deg)")
# ax_phase1.legend()
# sim.reset_meep()
# sim.run(until_after_sources=mp.stop_when_dft_decayed(tol=1e-4))
eps_data = sim.get_epsilon() #
ez_data = sim.get_dft_array(
whole_dft, mp.Ez, 0
) # Values for the component of the E-field in the z direction (in/out of screen)
# Creates the plot
ax_field = fig.add_subplot(1, 2, 2)
ax_field.set_title("Steady State Fields")
ax_field.imshow(np.transpose(eps_data), interpolation="spline36", cmap="binary")
ax_field.imshow(
np.flipud(np.transpose(np.real(ez_data))),
interpolation="spline36",
cmap="RdBu",
alpha=0.9,
)
ax_field.axis("off")
plt.show()
In-phase
constructive interference
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from gdsfactory.technology import LayerLevel, LayerStack
mp.verbosity(0)
# Set up frequency points for simulation
npoints = 100
lcen = 1.55
dlam = 0.02
wl = np.linspace(lcen - dlam / 2, lcen + dlam / 2, npoints)
fcen = 1 / lcen
fwidth = 3 * dlam / lcen**2
fpoints = 1 / wl # Center frequency
mode_parity = mp.EVEN_Y + mp.ODD_Z
dpml = 1
dpad = 1
resolution = 20
# Define materials
Si = mp.Medium(index=3.45)
SiO2 = mp.Medium(index=1.45)
cell_size = mp.Vector3(ybranch.xsize + 2 * dpml, ybranch.ysize + 2 * dpml + 2 * dpad, 0)
ybranch = gf.components.extend_ports(ybranch, port_names=["o1", "o2", "o3"], length=1)
ybranch = ybranch.copy()
ybranch.flatten()
ybranch.center = (0, 0)
geometry = gm.get_meep_geometry.get_meep_geometry_from_component(ybranch)
geometry = [
mp.Prism(geom.vertices, geom.height, geom.axis, geom.center, material=Si)
for geom in geometry
]
src = mp.GaussianSource(frequency=fcen, fwidth=fwidth)
source = [
mp.EigenModeSource(
src=src,
eig_band=1,
eig_parity=mode_parity,
eig_kpoint = mp.Vector3(-1,0,0),
direction = mp.NO_DIRECTION,
size=mp.Vector3(0, 1),
center=mp.Vector3(ybranch.ports["o2"].x - dpml - 1, ybranch["o2"].y),
amplitude=1
),
mp.EigenModeSource(
src=src,
eig_band=1,
eig_parity=mode_parity,
eig_kpoint = mp.Vector3(-1,0,0),
direction = mp.NO_DIRECTION,
size=mp.Vector3(0, 1),
center=mp.Vector3(ybranch.ports["o3"].x - dpml - 1, ybranch["o3"].y),
amplitude=1
),
]
sim = mp.Simulation(
resolution=resolution,
cell_size=cell_size,
boundary_layers=[mp.PML(dpml)], #
sources=source, # The sources
geometry=geometry, # The geometry
default_material=SiO2,
)
m1 = mp.Volume(
center=mp.Vector3(ybranch.ports["o1"].x + dpml + 1 + 0.5, ybranch["o1"].y),
size=mp.Vector3(0, 1),
)
m2 = mp.Volume(
center=mp.Vector3(ybranch.ports["o2"].x - dpml - 1 - 0.5, ybranch["o2"].y),
size=mp.Vector3(0, 1),
)
m3 = mp.Volume(
center=mp.Vector3(ybranch.ports["o3"].x - dpml - 1 - 0.5, ybranch["o3"].y),
size=mp.Vector3(0, 1),
)
mode_monitor_1 = sim.add_mode_monitor(fpoints, mp.ModeRegion(volume=m1))
mode_monitor_2 = sim.add_mode_monitor(fpoints, mp.ModeRegion(volume=m2))
mode_monitor_3 = sim.add_mode_monitor(fpoints, mp.ModeRegion(volume=m3))
whole_dft = sim.add_dft_fields([mp.Ez], fcen, 0, 1, center=mp.Vector3(), size=cell_size)
sim.plot2D(labels=False)
sim.run(until_after_sources=mp.stop_when_dft_decayed(tol=1e-4))
# Finds the S parameters
norm_mode_coeff = sim.get_eigenmode_coefficients(
mode_monitor_2, [1], eig_parity=mode_parity
).alpha[0, :, 1] + sim.get_eigenmode_coefficients(
mode_monitor_3, [1], eig_parity=mode_parity
).alpha[0, :, 1] # Adding both the ports input values
port1_coeff = (
sim.get_eigenmode_coefficients(mode_monitor_1, [1], eig_parity=mode_parity).alpha[
0, :, 1
]
/ norm_mode_coeff
)
port2_coeff = (
sim.get_eigenmode_coefficients(mode_monitor_2, [1], eig_parity=mode_parity).alpha[
0, :, 0
]
/ norm_mode_coeff
)
port3_coeff = (
sim.get_eigenmode_coefficients(mode_monitor_3, [1], eig_parity=mode_parity).alpha[
0, :, 0
]
/ norm_mode_coeff
)
# Calculates the transmittance based off of the S parameters
port1_trans = abs(port1_coeff) ** 2
port2_trans = abs(port2_coeff) ** 2
port3_trans = abs(port3_coeff) ** 2
insertion_loss_dB = 10*np.log10(port1_trans)
fig = plt.figure(figsize=(15, 4))
ax_loss = fig.add_subplot(1,2,1)
ax_loss.set_title("Insertion Loss P1")
ax_loss.plot(wl,insertion_loss_dB)
ax_loss.set_xlabel(r"Wavelength (\mu m)")
ax_loss.set_ylabel("Loss (dB)")
# ax_trans1 = fig.add_subplot(1, 3, 1)
# ax_trans1.set_title("Transmission per Port")
# ax_trans1.plot(wl, port1_trans, label=r"s1(23)^2") # Not the proper way to represent
# ax_trans1.plot(wl, port2_trans, label=r"s22^2")
# ax_trans1.plot(wl, port3_trans, label=r"s33^2")
# ax_trans1.set_xlabel(r"Wavelength (\mu m)")
# ax_trans1.set_ylabel(r"Transmission")
# ax_trans1.legend()
# ax_phase1 = fig.add_subplot(1, 3, 2)
# ax_phase1.set_title("Phase per Port")
# ax_phase1.plot(
# wl, np.unwrap(np.angle(port1_coeff) * 180 / np.pi), label=r"phase of s1(23)"
# )
# ax_phase1.plot(
# wl, np.unwrap(np.angle(port2_coeff) * 180 / np.pi), label=r"phase of s22"
# )
# ax_phase1.plot(
# wl, np.unwrap(np.angle(port3_coeff) * 180 / np.pi), label=r"phase of s33"
# )
# ax_phase1.set_xlabel(r"Wavelength (\mu m)")
# ax_phase1.set_ylabel("Angle (deg)")
# ax_phase1.legend()
# sim.reset_meep()
# sim.run(until_after_sources=mp.stop_when_dft_decayed(tol=1e-4))
eps_data = sim.get_epsilon() #
ez_data = sim.get_dft_array(
whole_dft, mp.Ez, 0
) # Values for the component of the E-field in the z direction (in/out of screen)
# Creates the plot
ax_field = fig.add_subplot(1, 2, 2)
ax_field.set_title("Steady State Fields")
ax_field.imshow(np.transpose(eps_data), interpolation="spline36", cmap="binary")
ax_field.imshow(
np.flipud(np.transpose(np.real(ez_data))),
interpolation="spline36",
cmap="RdBu",
alpha=0.9,
)
ax_field.axis("off")
plt.show()
Source Code
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norm_mode_coeff = sim.get_eigenmode_coefficients(
mode_monitor_3, [1], eig_parity=mode_parity
).alpha[0, :, 1]
port1_coeff = (
sim.get_eigenmode_coefficients(mode_monitor_1, [1], eig_parity=mode_parity).alpha[
0, :, 1
]
/ norm_mode_coeff
)
port1_trans = abs(port1_coeff) ** 2
insertion_loss_dB = 10*np.log10(port1_trans)
plt.plot(wl, insertion_loss_dB)
1
[<matplotlib.lines.Line2D at 0x7b118fc26fd0>]
Source Code
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plt.plot(wl, port1_trans)
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[<matplotlib.lines.Line2D at 0x7b118fca1d10>]
This post is licensed under CC BY 4.0 by the author.