tat_title_intro

main.tex

@@ -120,9 +120,9 @@
 \vspace{3cm}
 \sffamily
 \begin{tabular}{m{4.5cm} p{13.5cm} }
-  \includegraphics{head_foot/DOI} & \noindent\LARGE{\textbf{Photogenerated Electron-Hole Plasma-Induced Symmetry Breaking in Spherical Silicon Nanoparticles}} \\%Article title goes here instead of the text "This is the title"
+  \includegraphics{head_foot/DOI} & \noindent\LARGE{\textbf{Photo-generated Electron-Hole Plasma-Induced Symmetry Breaking in Spherical Silicon Nanoparticles}} \\%Article title goes here instead of the text "This is the title"
   \vspace{0.3cm} & \vspace{0.3cm} \\
-                                  & \noindent\large{Anton Rudenko,$^{\ast}$\textit{$^{a}$} Tatiana E. Itina,\textit{$^{a}$$^{b}$} Konstantin Ladutenko,\textit{$^{b}$} and Sergey Makarov\textit{$^{b}$}
+                                  & \noindent\large{Anton Rudenko,$^{\ast}$\textit{$^{a}$}  Konstantin Ladutenko,\textit{$^{b}$}  Sergey Makarov\textit{$^{b}$} and Tatiana E. Itina\textit{$^{a}$$^{b}$}
  
                                     \textit{$^{a}$~Laboratoire Hubert Curien, UMR CNRS 5516, University of Lyon/UJM, 42000, Saint-Etienne, France }
                                     \textit{$^{b}$~ITMO University, Kronverksiy pr. 49, St. Petersburg, Russia}
@@ -135,16 +135,16 @@ of nonlinear all-dielectric nanophotonics based on high refractive
 index (e.g., silicon) nanoparticles supporting magnetic optical
 response has recently emerged as a powerful tool for ultrafast
 all-optical modulation at nanoscale. A strong modulation can be
-achieved via photogeneration of dense electron-hole plasma in the
+achieved via photo-generation of dense electron-hole plasma in the
 regime of simultaneous excitation of electric and magnetic optical
 resonances, resulting in an effective transient reconfiguration of
-nanoparticle scattering properties. Because only homogenious plasma generation was previously considered in the photoexcited nanoparticle, a possibility of symmetry breaking, however, remain unexplored. To examine these effects, numerical modeling is performed. Based on the simulation results, we propose an original concept of a well-controlled deeply subwavelength
+nanoparticle scattering properties. Because only homogeneous plasma generation was previously considered in the photo-excited nanoparticle, a possibility of symmetry breaking, however, remain unexplored. To examine these effects, numerical modeling is performed. Based on the simulation results, we propose an original concept of a well-controlled deeply subwavelength
 ($\approx$$\lambda$$^3$/100) plasma-induced nanopatterning of
 spherical silicon nanoparticles. In particular, the revealed strong
 symmetry breaking in the initially symmetrical nanoparticle, which is observed during
 ultrafast photoexcitation near the magnetic dipole resonance, enables a considerable increase in the precision of laser-induced nanotreatment. Importantly, the proposed
 ultrafast manipulation of the nanoparticle inherent structure and symmetry 
-paves a way to the novel principles that are also promissing for nonlinear optical nanodevices.}
+paves a way to the novel principles that are also promising for nonlinear optical nanodevices.}
 
 \end{tabular}
 
@@ -226,19 +226,19 @@ distributions in silicon nanoparticle around a magnetic resonance.}
 
 Recently, femtosecond lasers have been used to ionize nanoparticles locally and to produce electron-hole plasmas (EHP) inside them, which have been directly observed by using plasma explosion imaging\cite{Hickstein2014}. Interestingly, inhomogeneous resonant scattering patterns have been experimentally revealed inside a single silicon nanoparticle\cite{Valuckas2017}.  
 
-In this Letter, we show that ultra-short laser-based EHP photoexcitation in
+In this Letter, we show that ultra-short laser-based EHP photo-excitation in
 a spherical semiconductor (e.g., silicon) nanoparticle leads to a strongly
-nonhomogeneous carrier distribution. To reveal and study this effect, we
- performe a full-wave numerical simulation of the intense
+inhomogeneous carrier distribution. To reveal and study this effect, we
+ perform a full-wave numerical simulation of the intense
 femtosecond (fs) laser pulse interaction with a silicon
 nanoparticle supporting Mie resonances and two-photon free carrier generation. In particular, we couple finite-difference time-domain (FDTD)
 method used to solve  Maxwell equations with kinetic equations describing
-nonlinear EHP generation.  Three dimentional transient variation of the material dielectric permittivity is calculated for nanoparticles of several sizes. The obtained results propose a novel strategy to create
-complicated nonsymmetrical nanostructures by using  photoexcited
+nonlinear EHP generation.  Three-dimensional transient variation of the material dielectric permittivity is calculated for nanoparticles of several sizes. The obtained results propose a novel strategy to create
+complicated non-symmetrical nanostructures by using  photo-excited
 single spherical silicon nanoparticles. Moreover, we show that dense EHP can
 be generated at deeply subwavelength scale
-($\approx$$\lambda$$^3$/100) supporting formation of small metallized
-parts inside the nanoparticle which transforms all-dielectric
+($\approx$$\lambda$$^3$/100) supporting formation of small metalized
+parts inside the nanoparticle, which transforms all-dielectric
 nanoparticle to a hybrid one that extends functionality of the ultrafast
 optical nanoantennas.
 
@@ -268,7 +268,7 @@ optical nanoantennas.
 
 We focus out attention on silicon because this material is promising
 for the implementation of numerous nonlinear photonic devices. This advantage is based on a broad
-range of optical nonlinearities, strong two-photon absorption, as well as a possibility of the photoinduced EHP
+range of optical nonlinearities, strong two-photon absorption, as well as a possibility of the photo-induced EHP
 excitation~\cite{leuthold2010nonlinear}. Furthermore, silicon
 nanoantennas demonstrate a sufficiently high damage threshold due to
 the large melting temperature ($\approx$1690~K), whereas its nonlinear
@@ -276,11 +276,11 @@ optical properties have been extensively studied during last
 decays~\cite{Van1987, Sokolowski2000, leuthold2010nonlinear}. High silicon melting point typically preserves structures formed from this material up to the EHP densities on the order of the critical value $n_{cr} \approx 5\cdot{10}^{21}$ cm$^{-3}$ \cite{Korfiatis2007}. At the critical density and above, silicon acquires metallic properties ($Re(\epsilon) < 0$) and contributes to the EHP reconfiguration during ultrashort laser irradiation.
 
 The process of three-dimensional photo-generation of the EHP in silicon
-nanoparticles has not been modelled before in time-domain. Therefore, herein we propose a model considering ultrashort laser interactions with a resonant silicon
+nanoparticles has not been modeled before in time-domain. Therefore, herein we propose a model considering ultrashort laser interactions with a resonant silicon
 sphere, where the EHP is generated via one- and two-photon absorption
 processes.  Importantly, we
 also consider nonlinear feedback of the material by taking into
-account the intraband light absorption on the generated free carriers. To simplify our model, we neglect free carrier diffusion at the considered short time scales. In fact, the aim of the present work is to study the EHP dynamics \textit{during} ultra-short laser interaction with the nanoparticle. The created electron-hole plasma then will recombine, however, as its existence madifies both laser-particle interaction and, hence, the following particle evolution.
+account the intraband light absorption on the generated free carriers. To simplify our model, we neglect free carrier diffusion at the considered short time scales. In fact, the aim of the present work is to study the EHP dynamics \textit{during} ultra-short laser interaction with the nanoparticle. The created electron-hole plasma then will recombine, however, as its existence modifies both laser-particle interaction and, hence, the following particle evolution.
 
 \subsection{Light propagation}
 
@@ -337,9 +337,9 @@ The changes of the real and imaginary parts of the permittivity associated with
 
 Fig. \ref{fig2} demonstrates the temporal evolution of the EHP generated inside the silicon
 nanoparticle of $R \approx 105$ nm. Here, irradiation by
-high-intensity, $I\approx $ from XXX to YYY (???), ultrashort laser Gaussian pulse is considered. Snapshots of free carrier density taken at different times correspond to different total amountof the deposited energy (different laser intensities). 
+high-intensity, $I\approx $ from XXX to YYY (???), ultrashort laser Gaussian pulse is considered. Snapshots of free carrier density taken at different times correspond to different total amount of the deposited energy (different laser intensities). 
 
-To better analyze the degree of inhomogenity,  we introduce the EHP asymmetry parameter, $G$, which is defined
+To better analyze the degree of inhomogeneity,  we introduce the EHP asymmetry parameter, $G$, which is defined
 as a relation between the average electron density generated in the
 front side of the nanoparticle and the average electron density in the
 back side, as shown in Fig. \ref{fig2}. During the femtosecond pulse
@@ -349,7 +349,7 @@ Far before the pulse peak shown in Fig. \ref{fig2}(a), the excitation
 processes follow the intensity distribution, generating a low-density
 electron plasma of a toroidal shape at magnetic dipole resonance
 conditions. For higher intensities, the optical properties of silicon
-change significantly according to the equations (\ref{Index}). As a result, the nonresonant electric dipole contributes to the forward shifting of EHP
+change significantly according to the equations (\ref{Index}). As a result, the non-resonant electric dipole contributes to the forward shifting of EHP
 density maximum. Therefore, EHP is localized in the front part of the
 nanoparticle, increasing the asymmetry factor $G$ in
 Fig. \ref{fig2}(b). Approximately at the pulse peak, the critical
@@ -392,8 +392,8 @@ nanoparticle for indicated radii (1-7).}
 We have discussed the EHP kinetics for a silicon nanoparticle of a fixed radius $R \approx 105$ nm. In what follows, we investigate the influence of the nanoparticle size on
 the EHP patterns and temporal evolution during ultrashort laser
 irradiation. A brief analysis of the initial intensity distribution
-inside the nanoparticle given by Mie theory for a spherical
-homogenneous nanoparticle \cite{Mie1908} can be useful in
+inside the nanoparticle given by the classical Mie theory for 
+homogeneous spherical particles \cite{Mie1908} can be useful in
 this case. Fig. \ref{fig3}(a, b) shows the scattering efficiency and
 the asymmetry parameter for forward/backward scattering for
 non-excited silicon nanoparticles of different radii calculated by Mie
@@ -431,6 +431,9 @@ nanoparticles, lower values of EHP asymmetry factor are obtained, as
 the electron density evolves not only from the intensity patterns in
 the front side of the nanoparticle but also in the back side.
 
+TODO: 
+Need to discuss agreement/differences between Mie and FDTD+rate. Anton ?!
+
 To demonstrate the effect of symmetry breaking, we calculate the
 intensity distribution around the nanoparticle for double-pulse
 experiment. The first pulse of larger pulse energy and polarization
@@ -503,7 +506,7 @@ can be also useful for beam steering, or for the enhanced second
 harmonics generation.
 
 \section{Acknowledgments} We gratefully acknowledge support from The French
-Ministry of Science and Education, from the French Center of Scientific Research (CNRS) and from the PHC Kolmogorov project "FORMALAS" .  
+Ministry of Science and Education, from the French Center of Scientific Research (CNRS) and from the PHC Kolmogorov project "FORMALAS".