Classical-quantum correspondence in atom ionization by midinfrared pulses

N. I. SHVETSOV-SHILOVSKI; D. G. ARBÓ; M. LEIN; K. TÕKÉSI; C. LEMELL; S. NAGELE; J. BURGDÖRFER

Frankfurt

Conferencia; 12th Eurepean Conference on Atoms, Molecules, and Photons; 2016

Goethe Universität

In recent years, the investigation of the photoionization process has gained renewed interest due to the development of few-cycle light sources with high intensity and improved observation tools for the fragmentation process. In parallel to experimental advances also refined theoretical methods have been developed to interpret the experimental results.While the solution of the time-dependent Schrödinger equation (TDSE), usually in single particle approximation can be compared directly with measured data, the applicability of quantum methods is limited by computational resources. Multiple ionization and large quiver amplitudesof electrons in mid-infrared fields remain a major challenge. Therefore, to support quantum simulations and provide a more intuitive interpretation of quantum results, (semi-)classical algorithms have been conceived which show a surprisingly good agreement with experimental [1] and with quantum results (e.g., the distribution of energies and angular momenta shown in Fig. 1 [2]) also in regimes where the applicability of classical methods is far from obvious.In this presentation I will give an overview over of our investigations on quantum-classical correspondence over a wide range of intensities and wavelengths [1,2] and discuss the extension of classical-trajectory Monte-Carlo (CTMC) simulations to also account for the semiclassical phase accumulated along the electron trajectory resulting in the observation of interferences in photoelectron spectra with near-perfect agreement between TDSE and CTMC results. These developments will allow for analysis of the photoionization process in parameter regimes not easily accessible to full solutions of the TDSE.[1] B. Wolter, C. Lemell, M. Baudisch, M. G. Pullen, X.-M. Tong, M. Hemmer, A. Senftleben, C. D. Schr¨oter, J. Ullrich, R. Moshammer, J. Biegert, and J. Burgd¨orfer, Phys. Rev. A 90, 063424 (2014).[2] D. G. Arb´o, C. Lemell, S. Nagele, N. Camus, L. Fechner, A. Krupp, T. Pfeifer, S. D. L´opez, R. Moshammer, and J. Burgd¨orfer, Phys. Rev. A 92, 023402 (2015).[3] N. I. Shvetsov-Shilovski, M. Lein, L. B. Madsen, E. Räasäanen, C. Lemell, J. Burgdörfer, D. G. Arbó, and K. Tokési, submitted to Phys. Rev. A (2016).