def vis():
### forces
fig, ax = plt.subplots()
force = np.zeros([3, len(separations)])
for i, separation in enumerate(separations):
var = job.load(sim, f'p{i}')
force[0, i] = var.Fx
force[1, i] = var.Fy
force[2, i] = var.Fz
norm = job.load(norm_sim)
ax.axhline(0, linestyle='--', color='black')
ax.plot(separations / nm,
force[0] / norm.norm * norm.area * constants.epsilon_0 / 2,
'o',
color='C0',
label='Fx (FDTD)')
ax.plot(separations / nm,
force[1] / norm.norm * norm.area * constants.epsilon_0 / 2,
'o',
color='C1',
label='Fy (FDTD)')
ax.plot(separations / nm,
force[2] / norm.norm * norm.area * constants.epsilon_0 / 2,
'o',
color='C2',
label='Fz (FDTD)')
import miepy
eps = meep_ext.get_eps(gold)(wavelength)
Au = miepy.constant_material(eps * scale**2)
water = miepy.constant_material(nb**2)
source = miepy.sources.rhc_polarized_plane_wave()
seps = np.linspace(300 * nm / scale, 900 * nm / scale, 100)
force = np.zeros([3, len(seps)])
for i, sep in enumerate(seps):
spheres = miepy.spheres([[-sep / 2, 0, 0], [sep / 2, 0, 0]],
radius / scale, Au)
sol = miepy.gmt(spheres, source, wavelength, 2, medium=water)
F = sol.force_on_particle(1)
force[:, i] = F.squeeze()
ax.plot(seps * scale / nm, force[0], color='C0', label='Fx (GMT)')
ax.plot(seps * scale / nm, force[1], color='C1', label='Fy (GMT)')
ax.plot(seps * scale / nm, force[2], color='C2', label='Fz (GMT)')
ax.set(xlabel='separation (nm)', ylabel='force')
ax.legend()
plt.show()
def vis():
### cross-sections
fig, ax = plt.subplots()
scat = np.zeros([len(separations)])
absorb = np.zeros([len(separations)])
for i, separation in enumerate(separations):
norm = job.load(norm_sim, f'p{i}')
var = job.load(sim, f'p{i}')
scat[i] = var.scattering / norm.norm * norm.area
absorb[i] = var.absorption / norm.norm * norm.area
ax.plot(separations / nm, scat, 'o', color='C0', label='scattering (FDTD)')
ax.plot(separations / nm,
absorb,
'o',
color='C1',
label='absorption (FDTD)')
ax.plot(separations / nm,
scat + absorb,
'o',
color='C2',
label='extinction (FDTD)')
import miepy
eps = meep_ext.get_eps(gold)(wavelength)
Au = miepy.constant_material(eps)
source = miepy.sources.rhc_polarized_plane_wave()
seps = np.linspace(300 * nm, 900 * nm, 100)
scat = np.zeros([len(seps)])
absorb = np.zeros([len(seps)])
extinct = np.zeros([len(seps)])
for i, sep in enumerate(seps):
spheres = miepy.spheres([[-sep / 2, 0, 0], [sep / 2, 0, 0]], radius,
Au)
sol = miepy.gmt(spheres, source, wavelength, 2)
scat[i], absorb[i], extinct[i] = sol.cross_sections()
ax.plot(seps / nm, scat, color='C0', label='scattering (GMT)')
ax.plot(seps / nm, absorb, color='C1', label='absorption (GMT)')
ax.plot(seps / nm, extinct, color='C2', label='extinction (GMT)')
ax.set(xlabel='separation (nm)', ylabel='cross-section')
ax.legend()
plt.show()
def vis():
### forces
fig, axes = plt.subplots(nrows=2, figsize=(7,6), sharex=True,
gridspec_kw=dict(height_ratios=[2,1], hspace=0.05))
force = np.zeros([3,len(separations)])
for i,separation in enumerate(separations):
var = job.load(sim, f'p{i}')
force[0,i] = var.Fx
force[1,i] = var.Fy
force[2,i] = var.Fz
norm = job.load(norm_sim)
for ax in axes:
ax.axhline(0, linestyle='--', color='black')
ax.plot(separations/nm, force[0]/norm.norm*norm.area*constants.epsilon_0/2*1e25, 'o', color='C0', label='Fx (FDTD)')
ax.plot(separations/nm, force[1]/norm.norm*norm.area*constants.epsilon_0/2*1e25, 'o', color='C1', label='Fy (FDTD)')
ax.plot(separations/nm, force[2]/norm.norm*norm.area*constants.epsilon_0/2*1e25, 'o', color='C2', label='Fz (FDTD)')
import miepy
eps = meep_ext.get_eps(gold)(wavelength)
Au = miepy.constant_material(eps)
# Au = miepy.constant_material(3.5**2)
source = miepy.sources.rhc_polarized_plane_wave()
seps = np.linspace(300*nm, 900*nm, 100)
force = np.zeros([3,len(seps)])
for i,sep in enumerate(seps):
spheres = miepy.spheres([[-sep/2,0,0],[sep/2,0,0]], radius, Au)
sol = miepy.gmt(spheres, source, wavelength, 2)
F = sol.force_on_particle(1)
force[:,i] = F.squeeze()
for ax in axes:
ax.plot(seps/nm, force[0]*1e25, color='C0', label='Fx (GMT)')
ax.plot(seps/nm, force[1]*1e25, color='C1', label='Fy (GMT)')
ax.plot(seps/nm, force[2]*1e25, color='C2', label='Fz (GMT)')
axes[0].legend()
axes[0].set(ylabel='force')
axes[1].set(xlabel='separation (nm)', ylabel='force', ylim=[-3e-2, 3e-2])
plt.show()
nm = 1e-9
sep = 50*nm
r = 20*nm
fig,axes = plt.subplots(nrows=2, figsize=plt.figaspect(2))
Nx = 180
Ny = 181
x = np.linspace(-sep/2 - 2*r, sep/2 + 2*r, Nx)
y = np.linspace(-2*r, 2*r, Ny)
z = 0
X,Y,Z = np.meshgrid(x,y,z, indexing='ij')
for i,sim in enumerate([True,False]):
system = miepy.gmt(miepy.spheres([[-sep/2,0,0],[sep/2,0,0]], r, miepy.materials. Ag()),
miepy.sources.plane_wave.from_string(polarization='x'),
600*nm, 2, interactions=sim)
E = np.squeeze(system.E_field(X,Y,Z,True))
I = np.sum(np.abs(E)**2, axis=0)
print(I.shape)
mask = np.zeros((Nx,Ny), dtype=bool)
mask[(np.squeeze(X)-sep/2)**2 + np.squeeze(Y)**2 < r**2] = True
mask[(np.squeeze(X)+sep/2)**2 + np.squeeze(Y)**2 < r**2] = True
I[mask] = 0
im = axes[i].pcolormesh(np.squeeze(X)/nm,np.squeeze(Y)/nm,I, shading='gouraud', rasterized=True)
plt.colorbar(im, ax=axes[i], label='Intensity')
axes[i].set(aspect='equal', xlabel='x (nm)', ylabel='y (nm)')
nm = 1e-9
r = 20 * nm
fig, axes = plt.subplots(ncols=2, figsize=plt.figaspect(1 / 2))
Nx = 50
Ny = 50
x = np.linspace(-5 * r, 5 * r, Nx)
y = np.linspace(-5 * r, 5 * r, Ny)
z = np.array([0])
X, Y, Z = np.meshgrid(x, y, z, indexing='xy')
R = (X**2 + Y**2 + Z**2)**0.5
THETA = np.arccos(Z / R)
PHI = np.arctan2(Y, X)
system = miepy.gmt(miepy.spheres([0, 0, 0], r, miepy.constant_material(1.3)),
miepy.sources.plane_wave.from_string(polarization='x'),
600 * nm,
2,
interactions=False)
E = np.squeeze(system.E_field(X, Y, Z, False))
I = np.sum(np.abs(E)**2, axis=0)
print(E[:, 0, 0])
mask = np.zeros((Nx, Ny), dtype=bool)
mask[(np.squeeze(Y))**2 + np.squeeze(X)**2 < 3.5 * r**2] = True
I[mask] = 0
im = axes[0].pcolormesh(np.squeeze(X) / nm,
np.squeeze(Y) / nm,
import numpy as np
import matplotlib.pyplot as plt
import miepy
from math import factorial
from tqdm import tqdm
from scipy import constants
nm = 1e-9
Ag = miepy.materials.Ag()
# Ag = miepy.constant_material(4**2 + 0.01j)
radius = 75 * nm
source = miepy.sources.rhc_polarized_plane_wave(amplitude=2)
separations = np.linspace(2 * radius + 10 * nm, 2 * radius + 700 * nm, 50)
spheres = miepy.spheres(
[[separations[0] / 2, 0, 0], [-separations[0] / 2, 0, 0]], radius, Ag)
mie = miepy.gmt(spheres, source, 600 * nm, 2)
analytic_force = np.zeros((3, ) + separations.shape)
analytic_torque = np.zeros_like(analytic_force)
mst_force = np.zeros_like(analytic_force)
mst_torque = np.zeros_like(analytic_force)
for i, separation in enumerate(tqdm(separations)):
mie.update_position(
np.array([[separation / 2, 0, 0], [-separation / 2, 0, 0]]))
analytic_force[:, i] = mie.force_on_particle(0).squeeze()
analytic_torque[:, i] = mie.torque_on_particle(0).squeeze()
mst_force[:, i], mst_torque[:, i] = map(
def vis():
### forces
fig, ax = plt.subplots()
norm = job.load(dimer_norm)
scat = job.load(dimer_scat)
ax.plot((1 / nm) / norm.frequency,
scat.scattering / norm.incident * norm.area,
'o',
color='C0',
label='scattering (FDTD)')
ax.plot((1 / nm) / norm.frequency,
scat.absorption / norm.incident * norm.area,
'o',
color='C1',
label='absorption (FDTD)')
ax.plot((1 / nm) / norm.frequency,
(scat.scattering + scat.absorption) / norm.incident * norm.area,
'o',
color='C2',
label='extinction (FDTD)')
import miepy
wavelengths = np.linspace(400 * nm, 1000 * nm, 100)
eps = meep_ext.get_eps(gold)(wavelengths)
Au = miepy.data_material(wavelengths, eps)
# Au = miepy.constant_material(3.5**2)
spheres = miepy.spheres([[-sep / 2, 0, 0], [sep / 2, 0, 0]], radius, Au)
source = miepy.sources.x_polarized_plane_wave()
sol = miepy.gmt(spheres, source, wavelengths, 2)
C, A, E = sol.cross_sections()
ax.axhline(0, linestyle='--', color='black')
ax.plot(wavelengths / nm, C, color='C0', label='scattering (GMT)')
ax.plot(wavelengths / nm, A, color='C1', label='absorption (GMT)')
ax.plot(wavelengths / nm, E, color='C2', label='extinction (GMT)')
ax.legend()
ax.set(xlabel='wavelength (nm)', ylabel='cross-section')
### field animation
fig, ax = plt.subplots()
x = np.linspace(0, cell[0] / nm, Nx)
z = np.linspace(0, cell[1] / nm, Nz)
X, Z = np.meshgrid(x, z, indexing='ij')
var = job.load(dimer_fields)
idx = np.s_[10:-10, 10:-10]
E = var.E[:, 10:-10, 10:-10]
# E = var.E
vmax = np.max(np.abs(E)) / 2
im = ax.pcolormesh(X[idx],
Z[idx],
E[0],
cmap='RdBu',
animated=True,
vmax=vmax,
vmin=-vmax)
ax.set_aspect('equal')
def update(i):
im.set_array(np.ravel(E[i][:-1, :-1]))
return [im]
ani = animation.FuncAnimation(fig,
update,
range(E.shape[0]),
interval=50,
blit=True)
plt.show()
def vis():
### forces
fig, axes = plt.subplots(nrows=2,
figsize=(7, 6),
sharex=True,
gridspec_kw=dict(height_ratios=[2, 1],
hspace=0.05))
norm = job.load(dimer_norm)
scat = job.load(dimer_scat)
for ax in axes:
ax.plot((1 / nm) / norm.frequency,
scat.Fx / norm.incident * norm.area * constants.epsilon_0 / 2 *
1e25,
'o',
color='C0',
label='Fx (FDTD)')
ax.plot((1 / nm) / norm.frequency,
scat.Fy / norm.incident * norm.area * constants.epsilon_0 / 2 *
1e25,
'o',
color='C1',
label='Fy (FDTD)')
ax.plot((1 / nm) / norm.frequency,
scat.Fz / norm.incident * norm.area * constants.epsilon_0 / 2 *
1e25,
'o',
color='C2',
label='Fz (FDTD)')
import miepy
wavelengths = np.linspace(400 * nm, 1000 * nm, 100)
eps = meep_ext.get_eps(gold)(wavelengths)
Au = miepy.data_material(wavelengths, eps)
# Au = miepy.constant_material(3.5**2)
spheres = miepy.spheres([[-sep / 2, 0, 0], [sep / 2, 0, 0]], radius, Au)
source = miepy.sources.rhc_polarized_plane_wave()
sol = miepy.gmt(spheres, source, wavelengths, 2)
F = sol.force_on_particle(1)
for ax in axes:
ax.axhline(0, linestyle='--', color='black')
ax.plot(wavelengths / nm, F[0] * 1e25, color='C0', label='Fx (GMT)')
ax.plot(wavelengths / nm, F[1] * 1e25, color='C1', label='Fy (GMT)')
ax.plot(wavelengths / nm, F[2] * 1e25, color='C2', label='Fz (GMT)')
axes[0].legend()
axes[0].set(ylabel='force')
axes[1].set(xlabel='wavelength (nm)', ylabel='force', ylim=[-0.035, 0.01])
### field animation
fig, ax = plt.subplots()
x = np.linspace(0, cell[0] / nm, Nx)
z = np.linspace(0, cell[1] / nm, Nz)
X, Z = np.meshgrid(x, z, indexing='ij')
var = job.load(dimer_fields)
idx = np.s_[10:-10, 10:-10]
E = var.E[:, 10:-10, 10:-10]
# E = var.E
vmax = np.max(np.abs(E)) / 2
im = ax.pcolormesh(X[idx],
Z[idx],
E[0],
cmap='RdBu',
animated=True,
vmax=vmax,
vmin=-vmax)
ax.set_aspect('equal')
def update(i):
im.set_array(np.ravel(E[i][:-1, :-1]))
return [im]
ani = animation.FuncAnimation(fig,
update,
range(E.shape[0]),
interval=50,
blit=True)
plt.show()
nm = 1e-9
sampling = 40
Nwav = 60
Au = miepy.materials.Au()
radius = 40 * nm
source = miepy.sources.x_polarized_plane_wave(amplitude=1)
# separations = np.linspace(2*radius+10e-9,2*radius+700e-9, 50)
wavelengths = np.linspace(300 * nm, 800 * nm, Nwav)
separation = 83 * nm
flux = np.zeros_like(wavelengths)
flux2 = np.zeros_like(wavelengths)
plt.figure()
for wav_idx, wav in enumerate(tqdm(wavelengths)):
spheres = miepy.spheres([[separation / 2, 0, 0], [-separation / 2, 0, 0]],
radius, Au)
sol = miepy.gmt(spheres, source, wav, 2, interactions=True)
scat = sol.scattering_cross_section()
flux2[wav_idx] = np.sum(scat)
# sol.update_position(np.array([[separation/2,0,0], [-separation/2,0,0]]))
r = 10000 * nm
THETA, PHI = sphere_mesh(sampling)
X, Y, Z = sph_to_cart(r, THETA, PHI)
E = sol.E_field(X, Y, Z, inc=False)
# H = sol.H_field(X,Y,Z, inc=False)
I = np.sum(np.abs(E)**2, axis=0).squeeze()
