Dissociation of H{sub 2}{sup +} and D{sub 2}{sup +} in an intense laser field

Journal Article · Mon Sep 01 04:00:00 EDT 1997 · Physical Review A

DOI:https://doi.org/10.1103/PhysRevA.56.2168· OSTI ID:560621

Ludwig, J; Rottke, H; Sandner, W ^[1]

---

1. Max-Born Institut, Rudower Chaussee 6, P.O. Box 1107, D-12474 Berlin (Germany)

We report experimental investigations on dissociation of H{sub 2} and D{sub 2} in intense subpicosecond laser pulses at 1053 and 526.5 nm. Intensities in the range from {approx}5{times}10{sup 13} up to {approx}5{times}10{sup 14} W/cm{sup 2} were applied. The kinetic-energy distributions of the photoions H{sup +} and D{sup +}, which change dramatically with the light pulse peak intensity, give a detailed insight into the dissociation mechanisms. At 526.5 nm and low light intensity, ions from bond-softening dissociation and probably seven-photon resonant dissociative multiphoton ionization dominate the spectra. The resonant intermediate states are Rydberg states of the neutral molecules. At 1053 nm, above-threshold dissociation makes the main contribution to the spectra. Independent of the excitation wavelength, Coulomb explosion dissociation is found in the high-intensity limit. H{sub 2}{sup +} and D{sub 2}{sup +} photoionization, triggering this process, proceeds in the quasistatic limit by preferred tunnel or above-barrier ionization in a limited range of internuclear separations around 7.5 a.u. The ion kinetic-energy distributions seem to indicate that at 526.5 nm ionization starts from molecular ions light stabilized in a certain range of internuclear distances. In contrast, at 1053 nm, ionization seems to start from dissociating molecular ions. {copyright} {ital 1997} {ital The American Physical Society}

• OSTI ID: 560621
• Journal Information: Physical Review A, Journal Name: Physical Review A Journal Issue: 3 Vol. 56; ISSN 1050-2947; ISSN PLRAAN
• Country of Publication: United States
• Language: English

Related Subjects

66 PHYSICS
CATIONS
DEUTERIUM
DEUTERIUM IONS
DISSOCIATION
HYDROGEN IONS
HYDROGEN IONS 2 PLUS
IONIZATION
LASER RADIATION
MULTI-PHOTON PROCESSES
PHOTON-MOLECULE COLLISIONS
RYDBERG STATES