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Bulletin of the Russian Academy of Sciences Physics

Generalized Langevin Dynamics in a Broadband Quantized Field

Andrew I. Trubilko

Published Jul 1, 2026• 0 citations
Publisher

Abstract

Abstract A generalized Langevin dynamics of a two-level system (atom, qubit) in a broadband quantized electromagnetic field is considered. The analysis is carried out using a kinetic equation of an open system, obtained based on a quantum stochastic differential equation. The latter is associated with the terms of the effective Hamiltonian of the problem up to the second order in the constant of interaction of the atom with the field.

DOI
10.1134/s1062873826700899

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The effects of the Stark interaction in the collective radiation of an ensemble of atoms in the field of a broadband electromagnetic field in a squeezed quantum state have been considered. It has been shown that the inclusion of the conditions for the formation of the squeezed field allows one to describe the dynamics of atoms in terms of random quantum creating, annihilating, and counting processes. The latter process is the Stark interaction of atoms and the field and manifests itself in the form of a trigger superradiance pulse generated by an ensemble of identical atoms excited by a quantized resonant squeezed electromagnetic field. The description is based on the kinetic equation derived for an open localized quantum system in a broadband squeezed quantized electromagnetic field. The resulting equation differs from the known ones, but agrees with them in particular and limiting cases.