We have calculated the total dielectronic recombination ͑DR͒ coefficients for the 2 P 1/2 and 2 P 3/2 states in B-like Ti 17ϩ , Fe 21ϩ , and Mo 37ϩ ions for electron temperatures 0.1рTр10 000 eV. The calculations are carried out using the multiconfiguration Dirac-Fock method in intermediate coupling with a configuration interaction. We find that accurate Coster-Kronig energies are critical for a successful determination of lowtemperature DR coefficients. We also find that the DR involving fine-structure excitations can be as important as the 2s-2p excitation channels in the low-temperature regime for some ions. ͓S1050-2947͑98͒02612-2͔
Using techniques of complex analysis in an algebraic approach, we solve the wave equation for a two-level atom interacting with a monochromatic light field exactly. A closed-form expression for the quasi-energies is obtained, which shows that the Bloch-Siegert shift is always finite, regardless of whether the original or the shifted level spacing is an integral multiple of the driving frequency, ω. We also find that the wave functions, though finite when the original level spacing is an integral multiple of ω, become divergent when the intensity-dependent shifted energy spacing is an integral multiple of the photon energy. This result provides, for the first time in the literature, an ab-initio theoretical explanation for the occurrence of the Freeman resonances observed in above-threshold ionization experiments. PACS number(s): 32.80. Rm, 42.65.Ky, 12.20Ds, 03.65.Nk
In this paper, a scaling law of photoionization of atoms irradiated by intense, few-cycle laser pulses is established. The scaling law sets a relation to the phase-dependent ionization with the kinetic energy of photoelectrons, the duration and peak intensity of short pulses, and the ionization potential of the target atoms. We find that it will be advantageous to manifest the phase-dependent photoionization by choosing the target atoms with larger ionization potential, using laser with smaller carrier-frequency, and increasing the pulse intensity.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.