Resonant inhibition of multiphoton ionization

Abstract

When exposed to intense light of -580 nm, the ground state of K shifts up in energy, passing through two-photon resonances with Rydberg states and finally crossing the two-photon ionization limit. Using laser pulses of 0.5 to 13 ps duration, we have shown experimentally that ionization occurs for short pulses, but for long pulses the population is diverted into the Rydberg states where some population survives the peak intensity of the pulse, in excellent agreement with a dynamic Floquet model.

Atomic hydrogen in a strong optical radiation field

“…In the case of hydrogen, however, the gaps at avoided crossings are very narrowand in fact the crossing with the 4f dressed state is not avoided in the real part. This suggests that adiabatic transfer of population to dressed excited states is less effective here than in the recent experiments in xenon [26] or potassium [27]. Moreover, for our hydrogenic case we expect any population in the dressed 4f, 5f, or 6f states to decay promptly after transfer from the dressed 1s state, because the lifetimes of these states at the crossings are only a few optical field cycles (e.g.…”

Ionization and fragmentation dynamics of benzene in intense laser fields by tandem mass spectroscopy

“…It was previously reported that the population trapping occurs in the Rydberg states of atoms [35][36][37][38] and diatomic molecules 39 in intense laser fields. This type of trapping is caused by the resonances between the Rydberg states, which are energetically shifted by the ac Stark effect, and the electronic ground state.…”

Rydberg excitation in xenon by the rising edge of a femtosecond laser pulse

“…Note added.-While preparing this manuscript we became aware of a similar experiment [8]. Story, Duncan, and Gallagher show that population is transferred during the rise of the pulse although their experimental circumstances were different.…”