#LyX 2.4 created this file. For more info see https://www.lyx.org/ \lyxformat 583 \begin_document \begin_header \save_transient_properties true \origin unavailable \textclass article \use_default_options true \maintain_unincluded_children false \language english \language_package default \inputencoding utf8 \fontencoding auto \font_roman "default" "TeX Gyre Pagella" \font_sans "default" "default" \font_typewriter "default" "default" \font_math "auto" "auto" \font_default_family default \use_non_tex_fonts false \font_sc false \font_roman_osf true \font_sans_osf false \font_typewriter_osf false \font_sf_scale 100 100 \font_tt_scale 100 100 \use_microtype false \use_dash_ligatures true \graphics default \default_output_format default \output_sync 0 \bibtex_command default \index_command default \float_placement class \float_alignment class \paperfontsize default \spacing single \use_hyperref true \pdf_author "Marek Nečada" \pdf_bookmarks true \pdf_bookmarksnumbered false \pdf_bookmarksopen false \pdf_bookmarksopenlevel 1 \pdf_breaklinks false \pdf_pdfborder false \pdf_colorlinks false \pdf_backref false \pdf_pdfusetitle true \papersize default \use_geometry false \use_package amsmath 1 \use_package amssymb 1 \use_package cancel 1 \use_package esint 1 \use_package mathdots 1 \use_package mathtools 1 \use_package mhchem 1 \use_package stackrel 1 \use_package stmaryrd 1 \use_package undertilde 1 \cite_engine basic \cite_engine_type default \biblio_style plain \use_bibtopic false \use_indices false \paperorientation portrait \suppress_date false \justification true \use_refstyle 1 \use_minted 0 \use_lineno 0 \index Index \shortcut idx \color #008000 \end_index \secnumdepth 3 \tocdepth 3 \paragraph_separation indent \paragraph_indentation default \is_math_indent 0 \math_numbering_side default \quotes_style english \dynamic_quotes 0 \papercolumns 1 \papersides 1 \paperpagestyle default \tablestyle default \tracking_changes false \output_changes false \html_math_output 0 \html_css_as_file 0 \html_be_strict false \end_header \begin_body \begin_layout Section Finite systems \end_layout \begin_layout Itemize motivation (classes of problems that this can solve: response to external radiation, resonances, ...) \begin_inset Separator latexpar \end_inset \end_layout \begin_deeper \begin_layout Itemize theory \begin_inset Separator latexpar \end_inset \end_layout \begin_deeper \begin_layout Itemize T-matrix definition, basics \begin_inset Separator latexpar \end_inset \end_layout \begin_deeper \begin_layout Itemize How to get it? \end_layout \end_deeper \begin_layout Itemize translation operators (TODO think about how explicit this should be, but I guess it might be useful to write them to write them explicitly (but in the shortest possible form) in the normalisation used in my program) \end_layout \begin_layout Itemize employing point group symmetries and decomposing the problem to decrease the computational complexity (maybe separately) \end_layout \end_deeper \end_deeper \begin_layout Subsection Motivation \end_layout \begin_layout Standard The basic idea of MSTMM is quite simple: the driving electromagnetic field incident onto a scatterer is expanded into a vector spherical wavefunction (VSWF) basis in which the single scattering problem is solved, and the scattered field is then re-expanded into VSWFs centered at the other scatterers. Repeating the same procedure with all (pairs of) scatterers yields a set of linear equations, solution of which gives the coefficients of the scattered field in the VSWF bases. However, \end_layout \begin_layout Subsection Single-particle scattering \end_layout \begin_layout Standard In order to define the basic concepts, let us first consider the case of EM radiation scattered by a single particle. We assume that the scatterer lies inside a closed sphere \begin_inset Formula $\particle$ \end_inset , the space outside this volume \begin_inset Formula $\medium$ \end_inset is filled with an homogeneous isotropic medium with relative electric permittiv ity \begin_inset Formula $\epsilon(\vect r,\omega)=\epsbg(\omega)$ \end_inset and magnetic permeability \begin_inset Formula $\mu(\vect r,\omega)=\mubg(\omega)$ \end_inset , and that the whole system is linear, i.e. the material properties of neither the medium nor the scatterer depend on field intensities. Under these assumptions, the EM fields in \begin_inset Formula $\medium$ \end_inset must satisfy the homogeneous vector Helmholtz equation \begin_inset Formula $\left(\nabla^{2}+k^{2}\right)\Psi\left(\vect r,\vect{\omega}\right)=0$ \end_inset \begin_inset Note Note status open \begin_layout Plain Layout todo define \begin_inset Formula $\Psi$ \end_inset , mention transversality \end_layout \end_inset with \begin_inset Formula $k=TODO$ \end_inset [TODO REF Jackson?]. Its solutions (TODO under which conditions? What vector space do the SVWFs actually span? Check Comment 9.2 and Appendix f.9.1 in Kristensson) \end_layout \begin_layout Standard Throughout this text, we will use the same normalisation conventions as in \begin_inset CommandInset citation LatexCommand cite key "kristensson_scattering_2016" literal "true" \end_inset . \end_layout \begin_layout Subsubsection Spherical waves \end_layout \begin_layout Standard \begin_inset Note Note status open \begin_layout Plain Layout TODO small note about cartesian multipoles, anapoles etc. (There should be some comparing paper that the Russians at META 2018 mentioned.) \end_layout \end_inset \end_layout \begin_layout Subsubsection T-matrix definition \end_layout \begin_layout Subsubsection Absorbed power \end_layout \begin_layout Subsubsection T-matrix compactness, cutoff validity \end_layout \begin_layout Subsection Multiple scattering \end_layout \begin_layout Subsubsection Translation operator \end_layout \begin_layout Subsubsection Numerical complexity, comparison to other methods \end_layout \end_body \end_document