Unify balls notations, some refs etc.

Former-commit-id: 69e5ae075b639a6aed4988b9e8801947017026a5
This commit is contained in:
Marek Nečada 2019-08-06 23:43:01 +03:00
parent 2b031d43da
commit 46b651d97f
3 changed files with 221 additions and 99 deletions

View File

@ -260,12 +260,12 @@ status open
\begin_inset FormulaMacro
\newcommand{\particle}{\mathrm{\Theta}}
\newcommand{\medium}{\Theta}
\end_inset
\begin_inset FormulaMacro
\newcommand{\medium}{\thespace\backslash\particle}
\newcommand{\mezikuli}[3]{\Theta_{#1,#2}\left(#3\right)}
\end_inset
@ -355,7 +355,7 @@ status open
\begin_inset FormulaMacro
\newcommand{\closedball}[2]{B_{#1}#2}
\newcommand{\closedball}[2]{\overline{B_{#1}\left(#2\right)}}
\end_inset
@ -566,7 +566,17 @@ The (somewhat underrated) T-matrix multiple scattering method (TMMSM) can
Here we extend the method to infinite periodic structures using Ewald-type
lattice summation, and we exploit the possible symmetries of the structure
to further improve its efficiency.
(SHOULD I MENTION ALSO THE CROSS SECTION FORMULAS IN THE ABSTRACT?)
\begin_inset Marginal
status open
\begin_layout Plain Layout
Should I mention also the cross sections formulae in abstract / intro?
\end_layout
\end_inset
\end_layout
\begin_layout Abstract
@ -736,11 +746,6 @@ Maybe put the numerical results separately in the end.
TODOs
\end_layout
\begin_layout Itemize
Consistent notation of balls.
How is the difference between two cocentric balls called?
\end_layout
\begin_layout Itemize
It could be nice to include some illustration (example array) to the introductio
n.
@ -752,26 +757,12 @@ Maybe mention that in infinite systems, it can be also much faster than
other methods.
\end_layout
\begin_layout Itemize
Translation operators: rewrite in sph.
harm.
convention independent form.
\end_layout
\begin_layout Itemize
Truncation notation.
\end_layout
\begin_layout Itemize
Example results!
\end_layout
\begin_layout Itemize
Figures.
\end_layout
\begin_layout Itemize
Concrete comparison with other methods.
Example results and benchmarks with BEM; figures!
\end_layout
\begin_layout Itemize

View File

@ -138,16 +138,40 @@ Single-particle scattering
\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 $\particle$
We assume that the scatterer lies inside a closed ball
\begin_inset Formula $\closedball{R^{<}}{\vect 0}$
\end_inset
, the space outside this volume
\begin_inset Formula $\medium$
of radius
\begin_inset Formula $R^{<}$
\end_inset
is filled with an homogeneous isotropic medium with relative electric permittiv
ity
and center in the origin of the coordinate system (which can be chosen
that way; the natural choice of
\begin_inset Formula $\closedball{R^{<}}{\vect 0}$
\end_inset
is the circumscribed ball of the scatterer) and that there exists a larger
open cocentric ball
\begin_inset Formula $\openball{R^{>}}{\vect 0}$
\end_inset
, such that
\begin_inset Marginal
status open
\begin_layout Plain Layout
Is there a word for this?
\end_layout
\end_inset
the (non-empty) volume
\begin_inset Formula $\mezikuli{R^{<}}{R^{>}}{\vect 0}=\openball{R^{>}}{\vect 0}\setminus\closedball{R^{<}}{\vect 0}$
\end_inset
is filled with a homogeneous isotropic medium with relative electric permittivi
ty
\begin_inset Formula $\epsilon(\vect r,\omega)=\epsbg(\omega)$
\end_inset
@ -285,7 +309,16 @@ where
\end_inset
are the regular spherical Bessel function and spherical Hankel function
of the first kind, respectively, as in [DLMF §10.47], and
of the first kind, respectively, as in
\begin_inset CommandInset citation
LatexCommand cite
after "§10.47"
key "NIST:DLMF"
literal "false"
\end_inset
, and
\begin_inset Formula $\vsh{\tau}lm$
\end_inset
@ -307,7 +340,16 @@ In our convention, the (scalar) spherical harmonics
\begin_inset Formula $\ush lm$
\end_inset
are identical to those in [DLMF 14.30.1], i.e.
are identical to those in
\begin_inset CommandInset citation
LatexCommand cite
after "14.30.1"
key "NIST:DLMF"
literal "false"
\end_inset
, i.e.
\begin_inset Formula
\[
\ush lm=\left(\frac{\left(l-m\right)!\left(2l+1\right)}{4\pi\left(l+m\right)!}\right)^{\frac{1}{2}}e^{im\phi}\dlmfFer lm\left(\cos\theta\right)
@ -319,8 +361,16 @@ where importantly, the Ferrers functions
\begin_inset Formula $\dlmfFer lm$
\end_inset
defined as in [DLMF §14.3(i)] do already contain the Condon-Shortley phase
defined as in
\begin_inset CommandInset citation
LatexCommand cite
after "§14.3(i)"
key "NIST:DLMF"
literal "false"
\end_inset
do already contain the Condon-Shortley phase
\begin_inset Formula $\left(-1\right)^{m}$
\end_inset
@ -418,7 +468,7 @@ The regular VSWFs
\begin_inset Formula $\vswfrtlm{\tau}lm\left(k\vect r\right)$
\end_inset
constitute a basis for solutions of the Helmholtz equation
would constitute a basis for solutions of the Helmholtz equation
\begin_inset CommandInset ref
LatexCommand eqref
reference "eq:Helmholtz eq"
@ -429,16 +479,17 @@ noprefix "false"
\end_inset
inside a ball
\begin_inset Formula $\openball 0{R^{>}}$
\begin_inset Formula $\openball{R^{>}}{\vect 0}$
\end_inset
with radius
\begin_inset Formula $R^{>}$
\end_inset
and center in the origin; however, if the equation is not guaranteed to
hold inside a smaller ball
\begin_inset Formula $B_{0}\left(R\right)$
and center in the origin, were it filled with homogeneous isotropic medium;
however, if the equation is not guaranteed to hold inside a smaller ball
\begin_inset Formula $\closedball{R^{<}}{\vect 0}$
\end_inset
around the origin (typically due to presence of a scatterer), one has to
@ -447,7 +498,7 @@ noprefix "false"
\end_inset
to have a complete basis of the solutions in the volume
\begin_inset Formula $\openball 0{R^{>}}\backslash B_{0}\left(R\right)$
\begin_inset Formula $\mezikuli{R^{<}}{R^{>}}{\vect 0}=\openball{R^{>}}{\vect 0}\setminus\closedball{R^{<}}{\vect 0}$
\end_inset
.
@ -469,11 +520,11 @@ The single-particle scattering problem at frequency
\end_inset
can be posed as follows: Let a scatterer be enclosed inside the ball
\begin_inset Formula $B_{0}\left(R\right)$
\begin_inset Formula $\closedball{R^{<}}{\vect 0}$
\end_inset
and let the whole volume
\begin_inset Formula $\openball 0{R^{>}}\backslash B_{0}\left(R\right)$
\begin_inset Formula $\mezikuli{R^{<}}{R^{>}}{\vect 0}$
\end_inset
be filled with a homogeneous isotropic medium with wave number
@ -482,7 +533,7 @@ The single-particle scattering problem at frequency
.
Inside
\begin_inset Formula $\openball 0{R^{>}}\backslash B_{0}\left(R\right)$
\begin_inset Formula $\mezikuli{R^{<}}{R^{>}}{\vect 0}$
\end_inset
, the electric field can be expanded as
@ -504,7 +555,7 @@ doplnit frekvence a polohy
\end_inset
If there was no scatterer and
\begin_inset Formula $B_{0}\left(R_{<}\right)$
\begin_inset Formula $\closedball{R^{<}}{\vect 0}$
\end_inset
was filled with the same homogeneous medium, the part with the outgoing
@ -513,7 +564,7 @@ If there was no scatterer and
\end_inset
due to sources outside
\begin_inset Formula $\openball 0R$
\begin_inset Formula $\openball{R^{>}}{\vect 0}$
\end_inset
would remain.
@ -670,7 +721,17 @@ literal "false"
\end_inset
-matrix results wrong; we found and fixed the bug and from upstream version
xxx onwards, it should behave correctly.
xxx
\begin_inset Marginal
status open
\begin_layout Plain Layout
Not yet merged to upstream.
\end_layout
\end_inset
onwards, it should behave correctly.
\end_layout
@ -689,8 +750,25 @@ The magnitude of the
\begin_inset Formula $T$
\end_inset
-matrix of a bounded scatterer is a compact operator [REF???], so from certain
multipole degree onwards,
-matrix of a bounded scatterer is a compact operator
\begin_inset CommandInset citation
LatexCommand cite
key "ganesh_convergence_2012"
literal "false"
\end_inset
\begin_inset Note Note
status open
\begin_layout Plain Layout
TODO
\end_layout
\end_inset
, so from certain multipole degree onwards,
\begin_inset Formula $l,l'>L$
\end_inset
@ -725,16 +803,6 @@ The magnitude of the
\end_inset
will also be negligible.
\begin_inset Note Note
status open
\begin_layout Plain Layout
TODO when it will not be negligible
\end_layout
\end_inset
\end_layout
\begin_layout Standard
@ -761,7 +829,7 @@ literal "false"
\end_inset
by requiring that
\begin_inset Formula $\delta\gtrsim\left(nR\right)^{L}/\left(2L+1\right)!!$
\begin_inset Formula $\delta\gg\left(nR\right)^{L}/\left(2L+1\right)!!$
\end_inset
, where
@ -886,7 +954,7 @@ literal "true"
.
Let the field in
\begin_inset Formula $\openball 0{R^{>}}\backslash B_{0}\left(R\right)$
\begin_inset Formula $\mezikuli{R^{<}}{R^{>}}{\vect 0}$
\end_inset
have expansion as in
@ -901,11 +969,11 @@ noprefix "false"
.
Then the net power transported from
\begin_inset Formula $B_{0}\left(R\right)$
\begin_inset Formula $\openball{R^{<}}{\vect 0}$
\end_inset
to
\begin_inset Formula $\openball 0{R^{>}}\backslash B_{0}\left(R\right)$
\begin_inset Formula $\mezikuli{R^{<}}{R^{>}}{\vect 0}$
\end_inset
via by electromagnetic radiation is
@ -917,7 +985,7 @@ P=\frac{1}{2k^{2}\eta_{0}\eta}\left(\Re\left(\rcoeffp{}^{\dagger}\outcoeffp{}\ri
\end_inset
In realistic scattering setups, power is transferred by radiation into
\begin_inset Formula $B_{0}\left(R\right)$
\begin_inset Formula $\openball{R^{<}}{\vect 0}$
\end_inset
and absorbed by the enclosed scatterer, so
@ -1087,25 +1155,15 @@ If the system consists of multiple scatterers, the EM fields around each
\end_inset
be an index set labeling the scatterers.
We enclose each scatterer in a ball
\begin_inset Formula $B_{\vect r_{p}}\left(R_{p}\right)$
We enclose each scatterer in a closed ball
\begin_inset Formula $\closedball{R_{p}}{\vect r_{p}}$
\end_inset
such that the balls do not touch,
\begin_inset Formula $B_{\vect r_{p}}\left(R_{p}\right)\cap B_{\vect r_{q}}\left(R_{q}\right)=\emptyset;p,q\in\mathcal{P}$
\begin_inset Formula $\closedball{R_{p}}{\vect r_{p}}\cap\closedball{R_{q}}{\vect r_{q}}=\emptyset;p,q\in\mathcal{P}$
\end_inset
,
\begin_inset Note Note
status open
\begin_layout Plain Layout
TODO bacha, musejí být uzavřené!
\end_layout
\end_inset
so there is a non-empty volume
, so there is a non-empty volume
\begin_inset Note Note
status open
@ -1116,12 +1174,20 @@ jaksetometuje?
\end_inset
\begin_inset Formula $\openball{\vect r_{p}}{R_{p}^{>}}\backslash B_{\vect r_{p}}\left(R_{p}\right)$
\begin_inset Formula $\mezikuli{R_{p}}{R_{p}^{>}}{\vect r_{p}}$
\end_inset
around each one that contains only the background medium without any scatterers.
Then the EM field inside each such volume can be expanded in a way similar
to
around each one that contains only the background medium without any scatterers
(we assume that all the volume outside
\begin_inset Formula $\bigcap_{p\in\mathcal{P}}\closedball{R_{p}}{\vect r_{p}}$
\end_inset
is filled with the same background medium).
Then the EM field inside each
\begin_inset Formula $\mezikuli{R_{p}}{R_{p}^{>}}{\vect r_{p}}$
\end_inset
can be expanded in a way similar to
\begin_inset CommandInset ref
LatexCommand eqref
reference "eq:E field expansion"
@ -1135,7 +1201,7 @@ noprefix "false"
\begin_inset Formula
\begin{align}
\vect E\left(\omega,\vect r\right) & =\sum_{\tau=1,2}\sum_{l=1}^{\infty}\sum_{m=-l}^{+l}\left(\rcoeffptlm p{\tau}lm\vswfrtlm{\tau}lm\left(k\left(\vect r-\vect r_{p}\right)\right)+\outcoeffptlm p{\tau}lm\vswfouttlm{\tau}lm\left(k\left(\vect r-\vect r_{p}\right)\right)\right),\label{eq:E field expansion multiparticle}\\
& \vect r\in\openball{\vect r_{p}}{R_{p}^{>}}\backslash B_{\vect r_{p}}\left(R_{p}\right).\nonumber
& \vect r\in\mezikuli{R_{p}}{R_{p}^{>}}{\vect r_{p}}.\nonumber
\end{align}
\end_inset
@ -1447,10 +1513,10 @@ reference "eq:translation operator"
below.
For singular (outgoing) waves, the form of the expansion differs inside
and outside the ball
\begin_inset Formula $\openball{\left\Vert \vect r_{2}-\vect r_{1}\right\Vert }{\vect r_{1}}:$
\begin_inset Formula $\closedball{\left\Vert \vect r_{2}-\vect r_{1}\right\Vert }{\vect r_{1}}$
\end_inset
:
\begin_inset Formula
\begin{eqnarray}
\vswfouttlm{\tau}lm\left(k\left(\vect r-\vect r_{1}\right)\right) & = & \begin{cases}
@ -1669,8 +1735,17 @@ and analogously the elements of the singular operator
\end_inset
where the constant factors in our convention read (TODO CHECK ONCE AGAIN
CAREFULLY FOR POSSIBLE PHASE FACTORS FACTORS)
where the constant factors in our convention read
\begin_inset Marginal
status open
\begin_layout Plain Layout
TODO check once again carefully for possible phase factors.
\end_layout
\end_inset
\begin_inset Note Note
status collapsed
@ -1979,8 +2054,8 @@ literal "false"
derives only the extinction cross section formula.
Let us re-derive it together with the many-particle scattering and absorption
cross sections.
First, let us take a ball circumscribing all the scatterers at once,
\begin_inset Formula $\openball R{\vect r_{\square}}\supset\particle$
First, let us take a ball containing all the scatterers at once,
\begin_inset Formula $\openball R{\vect r_{\square}}\supset\bigcup_{p\in\mathcal{P}}\closedball{R_{p}}{\vect r_{p}}$
\end_inset
.
@ -2010,8 +2085,7 @@ where
\begin_inset Formula $\outcoeffp{\square}$
\end_inset
using the translation operators (REF!!!) and use the single-scatterer formulae
using the translation operators and use the single-scatterer formulae
\begin_inset CommandInset ref
LatexCommand eqref
reference "eq:extincion CS single"
@ -2113,8 +2187,18 @@ noprefix "false"
where only the last expression is suitable for numerical evaluation with
truncated matrices, because the previous ones contain a translation operator
right next to an incident field coefficient vector (see Sec.
TODO).
right next to an incident field coefficient vector
\begin_inset Note Note
status open
\begin_layout Plain Layout
(see Sec.
TODO)
\end_layout
\end_inset
.
Similarly,
\begin_inset Formula
\begin{align}

View File

@ -175,10 +175,29 @@ superposition
\end_inset
-matrix method
\begin_inset Marginal
status open
\begin_layout Plain Layout
a.k.a.
something else?
\end_layout
\end_inset
\emph default
(TODO a.k.a something; refs??), and it has been implemented previously for
a limited subset of problems (TODO refs and list the limitations of the
available).
, and it has been implemented previously for a limited subset of problems
\begin_inset Marginal
status open
\begin_layout Plain Layout
Refs; list the limitations of available codes?
\end_layout
\end_inset
.
\begin_inset Note Note
status open
@ -237,18 +256,46 @@ We hereby release our MSTMM implementation, the
QPMS Photonic Multiple Scattering
\emph default
suite, as free software under the GNU General Public License version 3.
(TODO refs to the code repositories.) QPMS allows for linear optics simulations
of arbitrary sets of compact scatterers in isotropic media.
\begin_inset Marginal
status open
\begin_layout Plain Layout
TODO refs to the code repositories once it is published.
\end_layout
\end_inset
QPMS allows for linear optics simulations of arbitrary sets of compact
scatterers in isotropic media.
The features include computations of electromagnetic response to external
driving, the related cross sections, and finding resonances of finite structure
s.
Moreover, it includes the improvements covered in this paper, enabling
to simulate even larger systems and also infinite structures with periodicity
in one, two or three dimensions, which can be e.g.
used for quickly evaluating dispersions of such structures, and also their
topological invariants (TODO).
used for quickly evaluating dispersions of such structures
\begin_inset Marginal
status open
\begin_layout Plain Layout
And also their topological invariants (TODO)?
\end_layout
\end_inset
.
The QPMS suite contains a core C library, Python bindings and several utilities
for routine computations.
\begin_inset Marginal
status open
\begin_layout Plain Layout
Such as?
\end_layout
\end_inset
\begin_inset Note Note
status open