Open Access. Powered by Scholars. Published by Universities.®

Physical Sciences and Mathematics Commons

Open Access. Powered by Scholars. Published by Universities.®

Physics

PDF

University of Nebraska - Lincoln

Department of Physics and Astronomy: Faculty Publications

Series

2003

Articles 1 - 4 of 4

Full-Text Articles in Physical Sciences and Mathematics

Elucidating The Mechanisms Of Double Ionization Using Intense Half-Cycle, Single-Cycle, And Double Half-Cycle Pulses, G. Lagmago Kamta, Anthony F. Starace Oct 2003

Elucidating The Mechanisms Of Double Ionization Using Intense Half-Cycle, Single-Cycle, And Double Half-Cycle Pulses, G. Lagmago Kamta, Anthony F. Starace

Department of Physics and Astronomy: Faculty Publications

We investigate the interaction of a two-active electron system (Li-) with intense single-cycle and double half-cycle pulses. The ‘‘intensity’’ and ‘‘frequency’’ considered correspond to the ‘‘multiphoton above-barrier regime.’’ For the single-cycle pulse (SCP), the electric field changes sign once, allowing electron wave packets created during the first half cycle to recollide with the parent ion when driven back by the field. For the double half-cycle pulse (DHP), however, the electric field does not change sign, and electron wave packets created during the first half cycle are not driven back to the parent ion. We find that both single …


Controlling H- Detachment With Few-Cycle Pulses, S. X. Hu, Anthony F. Starace Oct 2003

Controlling H- Detachment With Few-Cycle Pulses, S. X. Hu, Anthony F. Starace

Department of Physics and Astronomy: Faculty Publications

We present a detailed analysis of short-pulse detachment processes using few-cycle pulses with the aim of demonstrating means for controlling such processes. We first generalize the standard Keldysh-type formalism for laser-target interactions (in which final-state interaction between the detached electron and the core is ignored) to include the possibility that the vector potential is nonzero at the end of the interaction between a short laser pulse and the target. With this formalism in hand, we examine the effects of half-cycle pulses (HCPs) on detachment of the prototypical negative ion H–, and show that detachment by pairs of oppositely-directed (i.e., "bidirectional") …


Static And Dynamic Dipole Polarizability Of The Helium Atom Using Wave Functions Involving Logarithmic Terms, Mauro Masili, Anthony F. Starace Jul 2003

Static And Dynamic Dipole Polarizability Of The Helium Atom Using Wave Functions Involving Logarithmic Terms, Mauro Masili, Anthony F. Starace

Department of Physics and Astronomy: Faculty Publications

We present a calculation of the static and dynamic dipole polarizability of the helium atom using a variationally stable treatment that incorporates the coupled-channel hyperspherical representation of the wave functions. Inclusion of logarithmic terms in intermediate functions as well as the effect of an optimization procedure for the variational parameter are analyzed. When available, our coupled-channel results are compared with other values in the literature.


Light Storage With Light Of Arbitrary Polarization, Hong Gao, Mark Rosenberry, Herman Batelaan Jan 2003

Light Storage With Light Of Arbitrary Polarization, Hong Gao, Mark Rosenberry, Herman Batelaan

Department of Physics and Astronomy: Faculty Publications

We have demonstrated the phase coherence of stored light in Rb vapor with a completely optical technique. Combining this technique with polarization measurements provides strong evidence that arbitrary polarizations can be stored. The fidelity obtained exceeds 95% for all polarizations. We view the capability to store polarizations as a first step towards building a quantum memory in such a system.