Liouville-space R-matrix-Floquet description of atomic radiative processes involving autoionizing states in the presence of intense electromagnetic fields

Jacobs, VL; Burke, PG; Potvliege, RM

Abstract

A reduced-density-operator description is developed for coherent optical phenomena in many-electron atomic systems, utilizing a Liouville-space, multiple-mode Floquet–Fourier representation. The Liouville-space formulation provides a natural generalization of the ordinary Hilbert-space (Hamiltonian) R-matrix-Floquet method, which has been developed for multi-photon transitions and laser-assisted electron–atom collision processes. In these applications, the R-matrix-Floquet method has been demonstrated to be capable of providing an accurate representation of the complex, multi-level structure of many-electron atomic systems in bound, continuum, and autoionizing states. The ordinary Hilbert-space (Hamiltonian) formulation of the R-matrix-Floquet method has been implemented in highly developed computer programs, which can provide a non-perturbative treatment of the interaction of a classical, multiple-mode electromagnetic field with a quantum system. This quantum system may correspond to a many-electron, bound atomic system and a single continuum electron. However, including pseudo-states in the expansion of the many-electron atomic wave function can provide a representation of multiple continuum electrons. The 'dressed' many-electron atomic states thereby obtained can be used in a realistic non-perturbative evaluation of the transition probabilities for an extensive class of atomic collision and radiation processes in the presence of intense electromagnetic fields. In order to incorporate environmental relaxation and decoherence phenomena, we propose to utilize the ordinary Hilbert-space (Hamiltonian) R-matrix-Floquet method as a starting-point for a Liouville-space (reduced-density-operator) formulation. To illustrate how the Liouville-space R-matrix-Floquet formulation can be implemented for coherent atomic radiative processes, we discuss applications to electromagnetically induced transparency, as well as to related pump–probe optical phenomena, and also to the unified description of radiative and dielectronic recombination in electron–ion beam interactions and high-temperature plasmas.

Citation

Jacobs, V., Burke, P., & Potvliege, R. (2014). Liouville-space R-matrix-Floquet description of atomic radiative processes involving autoionizing states in the presence of intense electromagnetic fields. Journal of Physics B: Atomic, Molecular and Optical Physics, 47(2), Article 025401. https://doi.org/10.1088/0953-4075/47/2/025401

• Journal Article Type: Article
• Acceptance Date: Nov 5, 2013
• Online Publication Date: Jan 8, 2014
• Publication Date: Jan 1, 2014
• Deposit Date: Dec 20, 2013
• Publicly Available Date: Jan 10, 2014
• Journal: Journal of Physics B: Atomic, Molecular and Optical Physics
• Print ISSN: 0953-4075
• Electronic ISSN: 1361-6455
• Publisher: IOP Publishing
• Peer Reviewed: Peer Reviewed
• Volume: 47
• Issue: 2
• Article Number: 025401
• DOI: https://doi.org/10.1088/0953-4075/47/2/025401
• Keywords: Atomic and molecular physics, Computational physics, Optics, quantum optics and lasers, Quantum information and quantum mechanics.
• Public URL: https://durham-repository.worktribe.com/output/1442898