Abstract The interaction of a single-photon broadband narrow-beam wave packet with an ensemble of localized atoms is considered. Simultaneously, this same ensemble interacts with a broadband quantized field in a vacuum state. The contribution of the packet action to the relaxation operator of an open system is presented.
Abstract The derived master kinetic equation is used to determine the features of the nature of an isolated object, an absorber, on which the state of a broadband single-photon excitation is transferred. In the role of the absorber, a quantum oscillator or a two-level atom is considered. It is shown that, in the case of a nonresonant interaction between the packet and an intermediary, and between the intermediary and the absorber, the transfer of the state of a single-photon packet is possible if the absorber is a quantum oscillator. In the case where the transfer is to a two-level atom, the excitation transfer is only partial.
It has been demonstrated that a quantum state of a broadband single-photon electromagnetic field can be detected and verified by recording the intensity of superradiance of an atomic ensemble governed by non- Wiener dynamics. Under these conditions, the collective relaxation of atoms in the Dike model into vacuum is completely suppressed and only the interaction of the external field with atoms generates a superradiance pulse proportional to the square of the number of atoms. In the case of a single-photon wave packet in a classical state prepared by weakening a broadband source of a family of independent coherent modes, incoherent emission of the same ensemble occurs with the intensity proportional to the number of atoms.
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.
Abstract Under the conditions of the Markov approximation, a master kinetic equation is derived that describes the transfer of the state of a single-photon packet to the state of a solitary object, depending on the nature of the latter. A single-photon excitation is a broadband packet with a Gaussian frequency distribution (an information signal) that interacts nonresonantly with a selected high-Q cavity mode (an intermediary). The latter also interacts nonresonantly with an absorber whose natural frequency is resonant to the central frequency of the packet.
Usually it is assumed that the stimulated emission appears as a consequence of the Bose—Einstein statistics of photons and that to observe this effect at least two excitations have to be initially present in the atom—field system. That is, both the atom and the electromagnetic field have to be excited. In this paper we show that stimulated emission can appear exclusively as a consequence of quantum interference in a system with just a single excitation. Specifically, we consider a single two-level atom which is initially in its lower energy state and it interacts with a single-photon multi-mode wave packet. We show that for a proper choice of the photon-wave packet the atom can exhibit stimulated emission.