Related papers: Enhanced Population on Ionic Excited States by Syn…
Utilizing a benchmark measurement of laser-induced ionization of an H$_2^+$ molecular ion beam target at infrared wavelength around 2 $\mu$m, we show that the characteristic two-peak structure predicted for laser-induced enhanced ionization…
An effective scheme of synchronized laser-triggered ion acceleration and the corresponding theoretical model are proposed for a slow light pulse of relativistic intensity, which penetrates into a near-critical-density plasma, strongly…
Dipole-dipole interactions are at the origin of long-lived collective atomic states, often called subradiant, which are explored for their potential use in novel photonic devices or in quantum protocols. Here, we study subradiance beyond…
High-resolution photoelectron momentum distributions of Xe atoms ionized by 800-nm linearly polarized laser fields have been traced at intensities from 1.1*1013 to 3.5*1013W/cm2 using velocity-map imaging techniques. At certain laser…
We study the generation of paired photons due to the effect of four-wave mixing in an ensemble of pumped two-level systems that decay via an intermediate metastable state. The slow population relaxation of the metastable state to the ground…
The ion acceleration driven by a laser pulse at intensity $I = 10^{20} - 10^{22} $W/cm$^2\times(\mu$m$/\lambda)^2$ from a double layer target is investigated with multi-parametric Particle-in-Cell (PIC) simulations. For targets with a wide…
The implementation of a superradiant laser as an active frequency standard is predicted to provide better short-term stability and robustness to thermal and mechanical fluctuations when compared to standard passive optical clocks. However,…
The dynamics of molecular electron excitation and ionisation is studied in real-time for ultra-short IR laser pulses of intensity I>10^{13} W/cm^{2}. The multi-electron molecule is modeled by a system of two active electrons moving in a…
Structured light has attracted great interest in scientific and technical fields. Here, we demonstrate the first generation of structured air lasing in N2+ driven by 800 nm femtosecond laser pulses. By focusing a vortex pump beam at 800 nm…
We discuss the production of ultracold molecules in their electronic ground state by photoassociation employing electronically excited states with ion-pair character and strong spin-orbit interaction. A short photoassociation laser pulse…
We demonstrate how the shape of femtosecond laser pulses can be tailored in order to obtain maximal ionization of atoms or molecules. For that purpose, we have overlayed a direct-optimization scheme on top of a fully unconstrained…
In this article we present a comprehensive theoretical investigation of phonon lasing with mixed-species trapped ions, as demonstrated in [T. Behrle, Phys. Rev. Lett. 131 (2023)], employing both a semi-classical mean-field description and a…
We report on the observation of backward lasing at 391.4 nm of nitrogen ions pumped by linearly polarized intense femtosecond pulses at 800 nm. The strongly enhanced spectral intensity at 391.4 nm, as well as the amplification of an…
We present theoretical and experimental results of coherent population trapping spectra on a multi-level $^{40}$Ca$^+$-type configuration, adding a third beam to the standard two-laser $\Lambda$ system to avoid undesired optical pumping. We…
The strong coupling between two autoionizing states in helium is studied theoretically with the pump-probe scheme. An isolated 100-as XUV pulse is used to excite helium near the 2s2p(1P) resonance state in the presence of an intense…
The ultrafast electronic and nuclear dynamics of H2 laser-induced double ionization is studied using a time-dependent wave packet approach that goes beyond the fixed nuclei approximation. The double ionization pathways are analyzed by…
We investigate dynamics of atomic and molecular systems exposed to intense, shaped chaotic fields and a weak femtosecond laser pulse theoretically. As a prototype example, the photoionization of a hydrogen atom is considered in detail. The…
We investigate the excitation of a three-level ladder-type atom by a unidirectional field with a pair of indistinguishable photons. Starting from an analytical expression for the two-photon absorption probability, we determine the…
A wavelength-degenerate pump-probe spectroscopy is used to study the ultrafast dynamics of strong-field ionization in femtosecond-laser subwavelength-structured fused silica. The comparative spectra demonstrate that femtosecond-laser…
We study the enhancement of the magnetic dipole induced excitation probability of the hyperfine ground state of Doppler-broadened muonic hydrogen ($p \mu^{-}$) by a nanosecond laser pulse in the mid-infrared range with Gaussian temporal…