Separation of Recollision Mechanisms in Nonsequential Strong Field Double Ionization of Ar: The Role of Excitation Tunneling

Feuerstein, B.; Moshammer, R.; Fischer, Daniel; Dorn, Alexander; Schröter, C. D.; Deipenwisch, J.; López‐Urrutia, J. R. Crespo; Höhr, C.; Neumayer, P.; Ullrich, J.; Rottke, H.; Trump, C.; Wittmann, M.; Korn, G.; Sandner, W.

doi:10.1103/physrevlett.87.043003

Cited by 336 publications

(185 citation statements)

References 19 publications

Supporting

Mentioning

169

Contrasting

Unclassified

Order By: Relevance

“…In the present intensity regime, essentially two mechanisms may contribute: the first is the (e, 2e)-mechanism, in which the recolliding electron directly promotes a second electron into the continuum via electron impact ionization 23 . The second is recollision-induced excitation with subsequent ionization (RESI) 24,25 , where the recolliding electron excites the parent ion, which is subsequently ionized by the laser field as depicted in Fig. 2a.…”

Section: Resultsmentioning

confidence: 99%

Attosecond tracing of correlated electron-emission in non-sequential double ionization

et al. 2012

View full text Add to dashboard Cite

Despite their broad implications for phenomena such as molecular bonding or chemical reac tions, our knowledge of multi electron dynamics is limited and their theoretical modelling remains a most difficult task. From the experimental side, it is highly desirable to study the dynamical evolution and interaction of the electrons over the relevant timescales, which extend into the attosecond regime. Here we use near single cycle laser pulses with well defined electric field evolution to confine the double ionization of argon atoms to a single laser cycle. The measured two electron momentum spectra, which substantially differ from spectra recorded in all previous experiments using longer pulses, allow us to trace the correlated emission of the two electrons on sub femtosecond timescales. The experimental results, which are discussed in terms of a semiclassical model, provide strong constraints for the development of theories and lead us to revise common assumptions about the mechanism that governs double ionization.

show abstract

Section: Resultsmentioning

confidence: 99%

Attosecond tracing of correlated electron-emission in non-sequential double ionization

et al. 2012

View full text Add to dashboard Cite

show abstract

“…Recollision-excitation with subsequent field ionisation (RESI) was first proposed by Feuerstein et al [68] and takes place when the kinetic energy of the electron is below I + p . In this case the ion is lifted to an excited state upon recollision, such that it can be field-ionised near one of the subsequent peaks of the laser field.…”

Section: Nonsequential Double Ionisationmentioning

confidence: 99%

“…Generally, low intensities at a fixed wavelength imply a shift towards the multiphoton regime, favouring excitation over direct impact ionisation. Starting from a low intensity, recollision excitation with subsequent field ionisation (RESI) [68] will dominate until the recollision energy exceeds the second ionisation potential I + p . Here, direct impact ionisation becomes possible [71,75] (see fig 6.1).…”

Section: Nonsequential Double Ionisationmentioning

confidence: 99%

“…This implies that the underlying double ionisation mechanism can consist of three possible channels illustrated in fig. 6.14: (i) TI from HOMO followed by impact ionization of the ionic X state, (ii) TI from HOMO-1 followed by impact ionization of the ionic A state, (iii) TI from HOMO followed by recollision excitation with subsequent field ionization (RESI) [68] via the ionic A state. Due to the high maximum recollision energy of E r 1350 ≈ 109 eV, all channels are open.…”

Section: Multichannel Nsdimentioning

confidence: 99%

“…In order to provide clear evidence for the recollision model and a separation of the two possible channels, numerous differential measurements of the recoil ion momentum in NSDI were performed [67][68][69][70][71]. Using a reaction microscope like in Cold Target Recoil Ion Momentum Spectroscopy (COLTRIMS, for a review see for example the article by Dörner et al [72], a simplified setup is illustrated in figure 2.5), the recoil momentum vectors of the doubly ionised ion and the two ejected electrons are determined via their position on the detector and time-of-flight (TOF).…”

Section: Nonsequential Double Ionisationmentioning

confidence: 99%

See 2 more Smart Citations

Resolving Strong Field Dynamics in Cation States of CO_2 via Optimised Molecular Alignment

Oppermann

2014

Springer Theses

View full text Add to dashboard Cite

In this thesis, the role of the molecular structure in strong field induced processes in CO 2 is resolved by the use of optimised impulsive molecular alignment. Two processes were investigated: recollision induced ionisation and the dissociation of the molecular ion CO + 2 . Both processes are driven by the initial tunneling ionisation of CO 2 . Through the use of molecular alignment, the orbital symmetries of the involved molecular ionic states were resolved, revealing the internal molecular dynamics in the form of ionisation and excitation pathways.A novel data analysis procedure was developed to extract the alignment distribution and rotational temperature of the impulsively aligned molecular ensemble. This facilitated the optimisation of molecular alignment in mixed gas samples and was demonstrated for N 2 , O 2 and CO 2 seeded in Ar.The recollision induced or nonsequential double ionisation (NSDI) of CO 2 was then studied in the molecular frame. The process was fully characterised by measuring the shape of the recolliding electron wavepacket and the angularly resolved inelastic electronion recollision cross section. The results reveal the contribution from both the ionic ground and first excited state of CO + 2 to the NSDI mechanism. This study was extended to the strong field induced dissociation of impulsively aligned CO + 2 . It was found that dissociation is driven by a parallel dipole transition from the second excited ionic state B to the predissociating state C, whilst recollision excitation was shown to not play a role. The strong field induced coupling of the ionic states B and C could thus be controlled by the laser polarisation.The results obtained in this thesis further the understanding of population dynamics of cation states in strong field processes. This is of special interest for extending molecular strong field physics to the study of electronic degrees of freedom and their coupling to the nuclear motion. had hoped for in a research degree and I cannot thank Jon enough for making it such an enriching experience, both professionally and personally.

show abstract

Ion-Generated, Attosecond Pulses: Interaction with Atoms and Comparison to Femtosecond Laser Fields

Ullrich

Voitkiv

2008

Strong Field Laser Physics

View full text Add to dashboard Cite

Separation of Recollision Mechanisms in Nonsequential Strong Field Double Ionization of Ar: The Role of Excitation Tunneling

Cited by 336 publications

References 19 publications

Attosecond tracing of correlated electron-emission in non-sequential double ionization

Attosecond tracing of correlated electron-emission in non-sequential double ionization

Resolving Strong Field Dynamics in Cation States of CO_2 via Optimised Molecular Alignment

Ion-Generated, Attosecond Pulses: Interaction with Atoms and Comparison to Femtosecond Laser Fields

Contact Info

Product

Resources

About