Physics Commons^™

Above-Threshold Ionization As Temporal Multi-Slit Interference, William B. Laing Iii

Faculty Works

When atoms are subjected to a laser pulse of sufficiently high intensity, electrons are ionized by absorbing multiple photons in excess of the ionization potential. The resulting sequence of peaks in the photoelectron spectrum separated by the energy of one photon is called “above-threshold ionization” (ATI). This time-independent description of ATI invokes the language of photons, even though calculations are performed using the time-dependent Schrodinger equation with a classical electric field. We demonstrate that the energy-periodic structure of ATI can be understood from the interference of ionized electron wavepackets produced periodically each half-cycle of the laser field. Using this simple …

Above-Threshold Ionization As Temporal Multi-Slit Interference, William B. Laing Iii, B.D. Esry

Faculty Works

When atoms are subjected to a laser pulse of sufficiently high intensity, electrons are ionized by absorbing multiple photons in excess of the ionization potential. The resulting sequence of peaks in the photoelectron spectrum separated by the energy of one photon is called ``above-threshold ionization'' (ATI). This time-independent description of ATI invokes the language of photons, even though calculations are performed using the time-dependent Schrodinger equation with a classical electric field. We demonstrate that the energy-periodic structure of ATI can be understood from the interference of ionized electron wavepackets produced periodically each half-cycle of the laser field. Using this simple …

Why Do Molecules Echo Atomic Periodicity?, Ray Hefferlin, Jonathan Sackett, Jeremy Tatum

Faculty Works

Franck–Condon factors are investigated for sequences of free

main-group diatomic molecules. Theory-based Condon loci

(parabolas) and Morse-potential loci are plotted on Deslandres

tables to verify if they, indeed, follow the largest Franck–Condon

factors. Then, the inclination angles of the Condon loci

are determined. Thus, entire band systems are quantified by

one variable, the angle. For all available isoelectronic sequences,

this angle increases from a central minimum toward

magic-number molecular boundaries. The theory for the Condon

locus gives the angle in terms of the ratio of the upperstate

to the lower-state force constants. It is concluded that

the periodicity is caused …