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@@ -309,11 +309,12 @@ where $\theta$ is the temporal pulse width at the half maximum (FWHM), $t_0$ is
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\subsection{Material ionization}
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To account for the material ionization that is induced by a sufficiently intense laser field inside the particle, we couple Maxwell's equations with the kinetic equation for the electron-hole plasma as follows
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-\begin{figure*}[ht!]
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-\centering
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-\includegraphics[width=120mm]{fig2.png}
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-\caption{\label{fig2} Free carrier density snapshots of electron plasma evolution inside Si nanoparticle taken a) $30$ fs b) $10$ fs before the pulse peak, c) at the pulse peak, d) $10$ fs e) $30$ fs after the pulse peak. Pulse duration $50$ fs (FWHM). Wavelength $800$ nm in air. Radius of the nanoparticle $R \approx 105$ nm, corresponding to the resonance condition. Graph shows the dependence of the asymmetric parameter of electron plasma density on the average electron density in the front half of the nanoparticle. $n_{cr} = 5\cdot{10}^{21}$ cm$^{-3}$ is the critical plasma resonance electron density for silicon.}
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-\end{figure*}
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+% \begin{figure*}[ht!]
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+% \centering
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+% \includegraphics[width=120mm]{fig2.png}
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+% \caption{\label{fig2} Free carrier density snapshots of electron plasma evolution inside Si nanoparticle taken a) $30$ fs b) $10$ fs before the pulse peak, c) at the pulse peak, d) $10$ fs e) $30$ fs after the pulse peak. Pulse duration $50$ fs (FWHM). Wavelength $800$ nm in air. Radius of the nanoparticle $R \approx 105$ nm, corresponding to the resonance condition. Graph shows the dependence of the asymmetric parameter of electron plasma density on the average electron density in the front half of the nanoparticle. $n_{cr} = 5\cdot{10}^{21}$ cm$^{-3}$ is the critical plasma resonance electron density for silicon.}
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+% \end{figure*}
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+
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The time-dependent conduction-band carrier density evolution is described by a rate equation that was proposed by van Driel \cite{Van1987}. This equation takes into account such processes as photoionization, avalanche ionization and Auger recombination, and is written as
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\begin{equation} \label{Dens} \displaystyle{\frac{\partial{n_e}}{\partial t} = \frac{n_a-n_e}{n_a}\left(\frac{\sigma_1I}{\hbar\omega} + \frac{\sigma_2I^2}{2\hbar\omega}\right) + \alpha{I}n_e - \frac{C\cdot{n_e}^3}{C\tau_{rec}n_e^2+1},} \end{equation}
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@@ -326,7 +327,8 @@ where $I=\frac{n}{2}\sqrt{\frac{\epsilon_0}{\mu_0}}\left|\vec{E}\right|^2$ is th
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\begin{figure*}[ht!]
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\centering
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-\includegraphics[width=0.9\textwidth]{Ne_105nm_800}
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+\includegraphics[width=0.9\textwidth]{2nm_75}
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+\includegraphics[width=0.9\textwidth]{2nm_115}
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\caption{\label{plasma-105nm} Split figure \ref{fig2} into two, this is first part.}
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\end{figure*}
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@@ -383,16 +385,16 @@ Of cause, this plasma is expected to diffuse after the considered time and turn
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\subsection{Effects of nanoparticle size/scattering efficiency factor
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on scattering directions}
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-\begin{figure}[ht] \centering
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-\includegraphics[width=90mm]{fig3.png}
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-\caption{\label{fig3} a) Scattering efficiency factor $Q_{sca}$
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-dependence on the radius $R$ of non-excited silicon nanoparticle
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-calculated by Mie theory; b) Parameter of forward/backward scattering
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-dependence on the radius $R$ calculated by Mie theory for non-excited
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-silicon nanoparticle c) Optimization parameter $K$ dependence on the
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-average electron density $n_e^{front}$ in the front half of the
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-nanoparticle for indicated radii (1-7).}
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-\end{figure}
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+% \begin{figure}[ht] \centering
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+% \includegraphics[width=90mm]{fig3.png}
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+% \caption{\label{fig3} a) Scattering efficiency factor $Q_{sca}$
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+% dependence on the radius $R$ of non-excited silicon nanoparticle
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+% calculated by Mie theory; b) Parameter of forward/backward scattering
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+% dependence on the radius $R$ calculated by Mie theory for non-excited
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+% silicon nanoparticle c) Optimization parameter $K$ dependence on the
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+% average electron density $n_e^{front}$ in the front half of the
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+% nanoparticle for indicated radii (1-7).}
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+% \end{figure}
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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
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the EHP patterns and temporal evolution during ultrashort laser
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@@ -458,13 +460,13 @@ nanoparticle is out of quasi-resonant condition and the intensity
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enhancements in Fig. \ref{fig4}(c) are weaker than in
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Fig. \ref{fig4}(b). Therefore, the generated nanoplasma acts like a quasi-metallic nonconcentric nanoshell inside the nanoparticle, providing a symmetry reduction \cite{Wang2006}.
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-\begin{figure}[ht] \centering
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-\includegraphics[width=90mm]{fig4.png}
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-\caption{\label{fig4} a) Electron plasma distribution inside Si
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-nanoparticle $R \approx 95$ nm $50$ fs after the pulse peak; (Kostya: Is it scattering field intensity snapshot XXX fs after the second pulse maxima passed the particle?) Intensity
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-distributions around and inside the nanoparticle b) without plasma, c)
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-with electron plasma inside.}
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-\end{figure}
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+% \begin{figure}[ht] \centering
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+% \includegraphics[width=90mm]{fig4.png}
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+% \caption{\label{fig4} a) Electron plasma distribution inside Si
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+% nanoparticle $R \approx 95$ nm $50$ fs after the pulse peak; (Kostya: Is it scattering field intensity snapshot XXX fs after the second pulse maxima passed the particle?) Intensity
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+% distributions around and inside the nanoparticle b) without plasma, c)
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+% with electron plasma inside.}
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+% \end{figure}
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%\begin{figure} %\centering
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% \includegraphics[height=0.7\linewidth]{Si-flow-R140-XYZ-Eabs}
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