misc/finiterectlat-modes.py

   1 #!/usr/bin/env python3
   2
   3 import math
   4 from qpms.argproc import ArgParser
   5
   6
   7 ap = ArgParser(['rectlattice2d_finite', 'single_particle', 'single_lMax', ])
   8
   9 ap.add_argument("-t", "--rank-tolerance", type=float, default=1e11)
  10 ap.add_argument("-c", "--min-candidates", type=int, default=1, help='always try at least this many eigenvalue candidates, even if their SVs in the rank tests are lower than rank_tolerance')
  11 ap.add_argument("-T", "--residual-tolerance", type=float, default=0.)
  12
  13 ap.add_argument("-o", "--output", type=str, required=False, help='output path (if not provided, will be generated automatically)')
  14 #ap.add_argument("-O", "--plot-out", type=str, required=False, help="path to plot output (optional)")
  15 #ap.add_argument("-P", "--plot", action='store_true', help="if -p not given, plot to a default path")
  16 #ap.add_argument("-g", "--save-gradually", action='store_true', help="saves the partial result after computing each irrep")
  17
  18 ap.add_argument("-f", "--centre", type=complex, required=True, help='Contour centre in eV')
  19 ap.add_argument("--ai", type=float, default=0.05, help="Contour imaginary half-axis in eV")
  20 ap.add_argument("--ar", type=float, default=0.05, help="Contour real half-axis in eV")
  21 ap.add_argument("-N", type=int, default="150", help="Integration contour discretisation size")
  22
  23 ap.add_argument("--irrep", type=str, default="none", help="Irrep subspace (irrep index from 0 to 7, irrep label, or 'none' for no irrep decomposition")
  24
  25 a=ap.parse_args()
  26
  27 import logging
  28 logging.basicConfig(format='%(asctime)s %(message)s', level=logging.INFO)
  29
  30 Nx, Ny = a.size
  31 px, py = a.period
  32
  33 particlestr = ("sph" if a.height is None else "cyl") + ("_r%gnm" % (a.radius*1e9))
  34 if a.height is not None: particlestr += "_h%gnm" % (a.height * 1e9)
  35 defaultprefix = "%s_p%gnmx%gnm_%dx%d_m%s_n%g_L%d_c(%s±%g±%gj)eV_cn%d" % (
  36     particlestr, px*1e9, py*1e9, Nx, Ny, str(a.material), a.refractive_index, a.lMax,
  37     str(a.centre), a.ai, a.ar, a.N)
  38 logging.info("Default file prefix: %s" % defaultprefix)
  39
  40 def inside_ellipse(point_xy, centre_xy, halfaxes_xy):
  41     x = point_xy[0] - centre_xy[0]
  42     y = point_xy[1] - centre_xy[1]
  43     ax = halfaxes_xy[0]
  44     ay = halfaxes_xy[1]
  45     return ((x/ax)**2 + (y/ay)**2) <= 1
  46
  47
  48 import numpy as np
  49 import qpms
  50 from qpms.cybspec import BaseSpec
  51 from qpms.cytmatrices import CTMatrix, TMatrixGenerator
  52 from qpms.qpms_c import Particle
  53 from qpms.cymaterials import EpsMu, EpsMuGenerator, LorentzDrudeModel, lorentz_drude
  54 from qpms.cycommon import DebugFlags, dbgmsg_enable
  55 from qpms import FinitePointGroup, ScatteringSystem, BesselType, eV, hbar
  56 from qpms.symmetries import point_group_info
  57 eh = eV/hbar
  58
  59 dbgmsg_enable(DebugFlags.INTEGRATION)
  60
  61 #Particle positions
  62 orig_x = (np.arange(Nx/2) + (0 if (Nx % 2) else .5)) * px
  63 orig_y = (np.arange(Ny/2) + (0 if (Ny % 2) else .5)) * py
  64
  65 orig_xy = np.stack(np.meshgrid(orig_x, orig_y), axis = -1)
  66
  67
  68 bspec = BaseSpec(lMax = a.lMax)
  69 medium = EpsMuGenerator(ap.background_epsmu)
  70 particles= [Particle(orig_xy[i], ap.tmgen, bspec) for i in np.ndindex(orig_xy.shape[:-1])]
  71
  72 sym = FinitePointGroup(point_group_info['D2h'])
  73 logging.info("Creating scattering system object")
  74 ss, ssw = ScatteringSystem.create(particles, medium, sym, a.centre * eh)
  75
  76 if a.irrep == 'none':
  77     iri = None # no irrep decomposition
  78     irname = 'full'
  79     logging.info("Not performing irrep decomposition and working with the full space of dimension %d." % ss.fecv_size)
  80 else:
  81     try:
  82         iri = int(a.irrep)
  83     except ValueError:
  84         iri = ss.irrep_names.index(a.irrep)
  85     irname = ss.irrep_names[iri]
  86     logging.info("Using irrep subspace %s (iri = %d) of dimension %d." % (irname, iri, ss.saecv_sizes[iri]))
  87
  88 outfile_tmp = defaultprefix + ".tmp" if a.output is None else a.output + ".tmp"
  89
  90 logging.info("Starting Beyn's algorithm")
  91 results = ss.find_modes(iri=iri, omega_centre = a.centre*eh, omega_rr=a.ar*eh, omega_ri=a.ai*eh, contour_points=a.N,
  92         rank_tol=a.rank_tolerance, rank_min_sel=a.min_candidates, res_tol=a.residual_tolerance)
  93 results['inside_contour'] = inside_ellipse((results['eigval'].real, results['eigval'].imag),
  94         (a.centre.real*eh, a.centre.imag*eh), (a.ar*eh, a.ai*eh))
  95 results['refractive_index_internal'] = [medium(om).n for om in results['eigval']]
  96
  97 outfile = defaultprefix + (('_ir%s_%s.npz' % (str(iri), irname)) if iri is not None else '.npz') if a.output is None else a.output
  98 np.savez(outfile, meta=vars(a), **results)
  99 logging.info("Saved to %s" % outfile)
 100
 101 exit(0)
 102
 103 # TODO plots.
 104 if a.plot or (a.plot_out is not None):
 105     import matplotlib
 106     matplotlib.use('pdf')
 107     from matplotlib import pyplot as plt
 108
 109     fig = plt.figure()
 110     ax = fig.add_subplot(111)
 111     ax.plot(sinalpha_list, σ_ext*1e12,label='$\sigma_\mathrm{ext}$')
 112     ax.plot(sinalpha_list, σ_scat*1e12, label='$\sigma_\mathrm{scat}$')
 113     ax.plot(sinalpha_list, σ_abs*1e12, label='$\sigma_\mathrm{abs}$')
 114     ax.legend()
 115     ax.set_xlabel('$\sin\\alpha$')
 116     ax.set_ylabel('$\sigma/\mathrm{\mu m^2}$')
 117
 118     plotfile = defaultprefix + ".pdf" if a.plot_out is None else a.plot_out
 119     fig.savefig(plotfile)
 120
 121 exit(0)
 122