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@@ -236,7 +236,7 @@ In this Letter, we show that ultra-short laser-based EHP photo-excitation in
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a spherical semiconductor (e.g., silicon) nanoparticle leads to a strongly
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inhomogeneous carrier distribution. To reveal and study this effect, we
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perform a full-wave numerical simulation of the intense
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-femtosecond (fs) laser pulse interaction with a silicon
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+femtosecond ($f\!s$) laser pulse interaction with a silicon
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nanoparticle supporting Mie resonances and two-photon free carrier generation. In particular, we couple finite-difference time-domain (FDTD)
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method used to solve Maxwell equations with kinetic equations describing
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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
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@@ -313,7 +313,7 @@ To account for the material ionization that is induced by a sufficiently intense
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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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+% \caption{\label{fig2} Free carrier density snapshots of electron plasma evolution inside Si nanoparticle taken a) $30\:f\!s$ b) $10\:f\!s$ before the pulse peak, c) at the pulse peak, d) $10\:f\!s$ e) $30\:f\!s$ after the pulse peak. Pulse duration $50\:f\!s$ (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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@@ -456,7 +456,7 @@ relaxation time of high electron density in silicon is $\tau_{rec} =
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6\cdot{10}^{-12}$ s \cite{Yoffa1980}, therefore, the
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electron density will not have time to decrease significantly for
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subpicosecond pulse separations. In our simulations, we use $\delta{t}
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-= 200$ fs pulse separation. The intensity distributions near the
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+= 200\:f\!s$ pulse separation. The intensity distributions near the
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silicon nanoparticle of $R = 95$ nm, corresponding to maxima value of
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$K$ optimization factor, without plasma and with generated plasma are
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shown in Fig. \ref{fig4}. The intensity distribution is strongly
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@@ -468,7 +468,7 @@ Fig. \ref{fig4}(b). Therefore, the generated nanoplasma acts like a quasi-metall
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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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+% nanoparticle $R \approx 95$ nm $50\:f\!s$ after the pulse peak; (Kostya: Is it scattering field intensity snapshot $XXX\:f\!s$ 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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@@ -490,9 +490,8 @@ like this: Small size will give as a magnetic dipole b1 resonance with
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Q-factor (ratio of wavelength to the resonance width at half-height)
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of about 8, a1 Q approx 4, the larger particle will have b2 Q approx
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40. For large particle we will have e.g. at R=238.4 second order b4
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-resonance with Q approx 800. As soon as the period at WL=800nm is 2.6
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-fs, we need about 25 fs pulse to pump dipole response, about 150 fs
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-for quadrupole, and about 2000fs for b4. If we think of optical
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+resonance with Q approx 800. As soon as the period at WL=800nm is $2.6\:f\!s$, we need about $25\:f\!s$ pulse to pump dipole response, about $150\:f\!s$
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+for quadrupole, and about $2000\:f\!s$ for b4. If we think of optical
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switching applications this is a rise-on time.
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TODO Kostya: Add discussion about mode selection due to the formation
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