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

Abstract

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Angular Distribution and Polarization of Superradiant Emission from Atomic Ensembles

“…We are particularly concerned with the many-atom states arising from the collective interaction of the atoms comprising the ensemble undergoing excitation in the presence of the incident laser fields. These states could be treated in a "dressed-state" representation induced by a classical timedependent field [24]. In the time-dependent description, it will not be necessary (and may not be appropriate) to assume that the excitation and radiative emission processes can be treated as independent events, a we did in the timeindependent description, since we can now include all modes of the time-dependent electromagnetic field, particularly the incident laser and vacuum fields, in the electromagnetic-interaction operator V(t).…”

“…The reduced, relevant Liouville-space resolvent (or Green) operator is expressed by , where is the relevant Liouvillian operator and is the Liouvillespace self-energy operator. The tetradic-matrix elements of the relevant Liouvillian operator may be obtained by means of the following commutation relationships: (24) The relevant Hamiltonian operator describes the many-particle quantum system together with the quantized electromagnetic field. The relevant Liouvillian operator can be decomposed as , where is the zeroorder (unperturbed) relevant Liouvillian operator corresponding to the zero-order relevant Hamiltonian operator and the Liouville-space perturbation operator describes the relevant electromagnetic interaction.…”