Plots the fields at r=0 for a point source in vacuum in cylindrical coordinates.

cyl_point_source_plot_r0.py

"""                                                                               
Plots the fields at r=0 for a point source in vacuum in cylindrical coordinates.  
"""

import meep as mp
import numpy as np
import matplotlib
matplotlib.use('agg')
import matplotlib.pyplot as plt

src_cmpt = mp.Er

res = 50.
dpml = 1.
s = 5.
m = +1
fcen = 1.

cell_size = mp.Vector3(s+dpml,0,s+2*dpml)

pml_layers = [
    mp.PML(dpml, direction=mp.R),
    mp.PML(dpml, direction=mp.Z),
]

sources = [
    mp.Source(
        src=mp.ContinuousSource(fcen),
        center=mp.Vector3(),
        component=src_cmpt,
    ),
]

sim = mp.Simulation(
    resolution=res,
    cell_size=cell_size,
    dimensions=mp.CYLINDRICAL,
    m=m,
    sources=sources,
    boundary_layers=pml_layers,
)

sim.run(until=56.5)

fig, ax = plt.subplots()
sim.plot2D(ax=ax)
if mp.am_master():
    fig.savefig(
        'cyl_plot2D.png',
        dpi=150,
        bbox_inches='tight',
    )

er = sim.get_array(
    component=mp.Er,
    center=mp.Vector3(),
    size=mp.Vector3(0,0,s),
    cmplx=True,
)

ep = sim.get_array(
    component=mp.Ep,
    center=mp.Vector3(),
    size=mp.Vector3(0,0,s),
    cmplx=True,
)

ez = sim.get_array(
    component=mp.Ez,
    center=mp.Vector3(),
    size=mp.Vector3(0,0,s),
    cmplx=True,
)

z = np.linspace(-0.5*s,0.5*s,len(er))

fig, ax = plt.subplots(ncols=3)
fig.subplots_adjust(wspace=0.4)
fig.suptitle('PR #2383')

ax[0].semilogy(z,np.abs(np.real(er)),'bo-.',label='$|\Re(E_r)|$')
ax[0].semilogy(z,np.abs(np.imag(er)),'ro--',label='$|\Im(E_r)|$')
ax[0].set_xlabel('z')
ax[0].set_ylabel('$E_r$ at $r=0$')
ax[0].set_title('$E_r$')
ax[0].legend(loc='lower center')

ax[1].semilogy(z,np.abs(np.real(ep)),'bo-.',label='$|\Re(E_\phi)|$')
ax[1].semilogy(z,np.abs(np.imag(ep)),'ro--',label='$|\Im(E_\phi)|$')
ax[1].set_xlabel('z')
ax[1].set_ylabel('$E_\phi$ at $r=0$')
ax[1].set_title('$E_\phi$')
ax[1].legend(loc='lower center')

ax[2].semilogy(z,np.abs(np.real(ez)),'bo-.',label='$|\Re(E_z)|$')
ax[2].semilogy(z,np.abs(np.imag(ez)),'ro--',label='$|\Im(E_z)|$')
ax[2].set_xlabel('z')
ax[2].set_ylabel('$E_z$ at $r=0$')
ax[2].set_title('$E_z$')
ax[2].legend(loc='lower center')

if mp.am_master():
    fig.savefig(
        f'cyl_Er_Ep_Ez_real_imag.png',
        dpi=150,
        bbox_inches='tight'
    )