Optimal Control of Ionization Processes in NaK:  Comparison between Theory and Experiment

Schäfer-Bung, Boris; Mitrić, Roland; Bonačić‐Koutecký, Vlasta; Bartelt, Andreas; Lupulescu, C.; Lindinger, Albrecht; Vajda, Štefan; Weber, Stefan; Wöste, L.

doi:10.1021/jp049153p

Cited by 53 publications

(50 citation statements)

References 37 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Among others a very important experimental work was conducted in the group of Wçste, in which they tried to optimize the photoionization yield from NaK with use of the genetic algorithm. [40] This was soon followed by a theoretical analysis by the group of Bonačić-Koutecký, [41] which clarified that the optimized process has been achieved in the series of resonant electronic excitation from the ground state (1 1 S + ) to intermediate excited states sequentially (!2 1 S + !3 1 P) and finally leading to the ionized state NaK + (1 2 S + ). Besides, in each intermediate electronic state the nuclear wavepacket running on it takes some time to move to a position where the succeeding electronic excitation has a large quantum mechanical probability.…”

Section: Introductionmentioning

confidence: 99%

Pulse‐Train Photoelectron Spectroscopy of Electronic and Nuclear Dynamics in Molecules

Arasaki

Takatsuka

2013

ChemPhysChem

View full text Add to dashboard Cite

We theoretically study the application of a femtosecond pulse train to simultaneously probe the electronic excitation dynamics and nuclear vibrational motion in the excited-state LiH molecule by means of time-resolved photoelectron spectroscopy. The step-like population transfers caused by continual interaction with a sequence of pulses and refractory periods are shown to give rise to time evolution of the photoelectron kinetic energy distribution as the history of molecular electronic and vibrational states. Such a signal should lead to a novel and direct way to investigate electronic and nuclear simultaneous dynamics involving multiple excited states.

show abstract

Section: Introductionmentioning

confidence: 99%

Pulse‐Train Photoelectron Spectroscopy of Electronic and Nuclear Dynamics in Molecules

Arasaki

Takatsuka

2013

ChemPhysChem

View full text Add to dashboard Cite

show abstract

“…Most of the subpulses can be assigned to multiples of 1 / 2·T osc of the wave packet in the first excited ⌺ state, which is about 220 fs. As observed before, 27 stepwise excitation is likely to yield more efficient production of NaK ions than just a single or double pulse. This assertion is true even if the respective pulse peak intensities are lower.…”

Section: Resultsmentioning

confidence: 58%

Parametric polarization pulse shaping demonstrated for optimal control of NaK

Weber

Plewicki

Weise

et al. 2008

The Journal of Chemical Physics

Self Cite

View full text Add to dashboard Cite

We present a routine for calculating and producing customized/parametric femtosecond laser pulses for investigating molecular processes involving the polarization. It is applied on the ionization of NaK molecules by feedback-loop optimization using the recently introduced double-pass "serial setup" that is capable of phase, amplitude, and polarization modulation. The temporal subpulse encoding uses the parameters distance, intensity, zero order spectral phase, and polarization state.

show abstract

“…Assuming the ansatz of controllability, i.e. the probability that a control target can be achieved with a laser controller [21], this allows, on the one hand, calculating optimal energy delivery [22,23] in the time domain for given objectives and, on the other hand, investigating active control knobs from temporal electric field distributions.…”

Section: Introductionmentioning

confidence: 99%

Guiding heat in laser ablation of metals on ultrafast timescales: an adaptive modeling approach on aluminum

et al. 2012

View full text Add to dashboard Cite

Using an optimal control hydrodynamic modeling approach and irradiation adaptive time-design, we indicate excitation channels maximizing heat load in laser ablated aluminum at low energy costs. The primary relaxation paths leading to an emerging plasma are particularly affected. With impulsive pulses on ps pedestals, thermodynamic trajectories are preferentially guided in ionized domains where variations in ionization degree occur. This impinges on the gas-transformation mechanisms and triggers a positive bremsstrahlung absorption feedback. The highest temperatures are thus obtained in the expanding ionized matter after a final impulsive excitation, as the electronic energy relaxes recombinatively. The drive relies on transitions to weakly coupled front plasmas at the critical optical density, favoring energy confinement with low mechanical work. Alternatively, robust collisional heating occurs in denser regions above the critical point. This impacts the nature, the excitation degree and the energy content of the ablated matter. Adaptive modeling can therefore provide optimal strategies with information on physical variables not readily accessible and, as experimentally confirmed, databases for pulse shapes with interest in remote spectroscopy, laser-induced matter transfer, laser material processing and development of secondary sources.

show abstract

Optimal Control of Ionization Processes in NaK: Comparison between Theory and Experiment

Cited by 53 publications

References 37 publications

Pulse‐Train Photoelectron Spectroscopy of Electronic and Nuclear Dynamics in Molecules

Pulse‐Train Photoelectron Spectroscopy of Electronic and Nuclear Dynamics in Molecules

Parametric polarization pulse shaping demonstrated for optimal control of NaK

Guiding heat in laser ablation of metals on ultrafast timescales: an adaptive modeling approach on aluminum

Contact Info

Product

Resources

About