One-dimensional Thomas-Fermi model of atoms, molecules, and small clusters exposed to an intense laser field

摘要: We have developed a one-dimensional time-dependent Thomas-Fermi model of atoms, molecules, and small clusters exposed to an intense subpicosecond laser field. In this model, the dynamics electronic cloud is governed by hydrodynamic equations motion, whereas nuclei move in accordance with Newton equations. The quantum mechanics enters approach only through constitutive relation between pressure density, which derived from application Fermi-Dirac statistics noninteracting $T=0$ temperature electron gas. time-independent version formulated terms integral equation for electric potential, also discussed. present numerical results diatomic molecules irradiated strong pulses. case we observe multielectron ionization accompanied dissociation. kinetic energy defect, understood as reduction resulting ions comparison simple Coulomb explosion picture, explained screening effect escaping fragments ejected electrons. For find that cluster has stepwise character; consecutive layers atoms are stripped off one one. highly energetic (as compared systems) atomic even relatively low intensities few clusters. Also, predicts nonuniform distribution among same charge state supports idea hot electrons generated via mechanism inverse bremsstrahlung.