相关论文: Optimizing the ionization and energy absorption of…
A detailed theoretical investigation of rare gas atom clusters under intense short laser pulses reveals that the mechanism of energy absorption is akin to {\it enhanced ionization} first discovered for diatomic molecules. The phenomenon is…
Rare gas or metal clusters are known to absorb laser energy very efficiently. Upon cluster expansion the Mie plasma frequency may become equal to the laser frequency. This linear resonance has been well studied both experimentally and…
The ionization dynamics of a Xenon cluster with 40 atoms is analyzed under a pum p probe scenario of laser pulses where an infrared laser pulse of 50 fs length follows with a well defined time delay a VUV pulse of the same length and peak…
For the energy absorption of atomic clusters as a function of the laser pulse duration we find a similar behavior as it has been observed for metallic clusters [K\"oller et al., Phys. Rev. Lett. {\bf 82}, 3783 (1999)]. In both situations…
The interaction of short laser pulses with small rare gas clusters is investigated by using a microscopic, semi-classical model with an explicit treatment of the inner-atomic dynamics. Field and collisional ionisation as well as…
Pronounced maximum absorption of laser light irradiating a rare-gas or metal cluster is widely expected during the linear resonance (LR) when Mie-plasma wavelength $\lambdaM$ of electrons equals the laser wavelength $\lambda$. On the…
Calculating the energy absorption of atomic clusters as a function of the laser pulse length $T$ we find a maximum for a critical $T^*$. We show that $T^*$ can be linked to an optimal cluster radius $R^*$. The existence of this radius can…
The motion of electrons and ions in medium-sized rare gas clusters (1000 atoms) exposed to intense laser pulses is studied microscopically by means of classical molecular dynamics using a hierarchical tree code. Pulse parameters for optimum…
Energy absorption of xenon clusters embedded in helium nanodroplets from strong femtosecond laser pulses is studied theoretically. Compared to pure clusters we find earlier and more efficient energy absorption in agreement with experiments.…
In a previous Letter [Phys. Rev. Lett. 96, 123401 (2006)] we have shown by means of three-dimensional particle-in-cell simulations and a simple rigid-sphere model that nonlinear resonance absorption is the dominant collisionless absorption…
A simple model is developed that quantitatively describes intense interactions of a VUV laser pulse with a xenon cluster. We find good agreement with a recent experiment [H. Wabnitz et al., Nature Vol. 420, 482 (2002)]. In particular, the…
Intense, ultrashort pulses of 800 nm laser light (12 fs, $\sim$4 optical cycles) of peak intensity 5$\times$10$^{14}$ W cm$^{-2}$ have been used to irradiate gas-phase Xe$_n$ clusters ($n$=500-25,000) so as to induce multiple ionization and…
Semi-classical molecular dynamics simulations of small rare gas clusters in short laser pulses of 100 nm wavelength were performed. For comparison, the cluster response to 800 nm laser pulses was investigated as well. The inner ionization…
Ion acceleration in the MeV range can be routinely achieved with table-top laser technology. One of the current challenges is to improve the energy coupling from the laser to the proton beam without increasing the laser peak power.…
We study collisionless absorption of short laser pulses of various intensity, wavelength ($\lambda$) and polarization in a deuterium cluster using molecular dynamics (MD) simulation. For a given laser energy and a pulse duration $\approx$…
The heating of ions via lower hybrid waves has been observed in several astrophysical as well as laboratory plasmas. We have conducted Particle-In-Cell simulations to demonstrate absorption of the incident laser pulse at a chosen localized…
Non-equilibrium processes following the irradiation of atomic clusters with short pulses of vacuum ultraviolet radiation are modelled using kinetic Boltzmann equations. The dependence of the ionization dynamics on the cluster size is…
Linear resonance (LR) absorption of an intense 800~nm laser light in a nano-cluster requires a long laser pulse > 100~fs when Mie-plasma frequency ($\omegaMie$) of electrons in the expanding cluster matches the laser frequency~($\omega$).…
Energy spectra and angular distributions have been measured of electrons that are emitted upon disassembly of $Xe_{150000}$ following irradiation by intense (10$^{15}-10^{16}$ W cm$^{-2}$) laser pulses whose durations are varied over the…
We describe how active feedback routines can be applied at limited repetition rate (5 Hz) to optimize high-power $>10$ TW) laser interactions with clustered gases. Optimization of x-ray production from an argon cluster jet, using a genetic…