Abstract In this introductory chapter, we consider the elementary radiative processes for both free atomic particles (atoms, ions, and molecules) and particles interacting with a monochromatic laser field. For more advanced considerations, the reader is advised to refer to the classical textbooks (Loudon 1973; Sargent et al. 1974; Allen and Eberly 1975; Sobelman 1979; Haken 1981; Knight and Allen 1983; Meystre and Sargent 1990; Cohen-Tannoudji et al. 1992; Foot 2004). Extensions of this material are treated in subsequent chapters, wherein various light field configurations, atomic particles, and the processes of interaction between atomic particles and laser fields are considered in detail.Abstract In this introductory chapter, we consider the elementary radiative processes for both free atomic particles (atoms, ions, and molecules) and particles interacting with a monochromatic laser field. For more advanced considerations, the reader is advised to refer to the classical textbooks (Loudon 1973; Sargent et al. 1974; Allen and Eberly 1975; Sobelman 1979; Haken 1981; Knight and Allen 1983; Meystre and Sargent 1990; Cohen-Tannoudji et al. 1992; Foot 2004). Extensions of this material are treated in subsequent chapters, wherein various light field configurations, atomic particles, and the processes of interaction between atomic particles and laser fields are considered in detail.

Feb 15, 20070 citations

Atomic Radiative Processes

Elsevier eBooksJan 1, 198221 citations

Elementary processes with two quantum transitions

M. Göppert-Mayer

Annalen der PhysikJul 30, 2009108 citations

Superoperators and their implications in the hybrid model for photodetection

Ching Tsung Lee

The external photodetection of cavity radiation is considered as a continuous quantum measurement in the sense of Srinivas and Davies [Opt. Acta 28, 981 (1981)]. It is analyzed in terms of three elementary processes: the no-leak process, the one-leak-undetected process, and the one-leak-detected process. The first two form a no-count process and the last one, a one-count process. Superoperators for these elementary processes are postulated, following the examples of Srinivas and Davies. The superoperators for the one-count process, the no-count process, the m-count process, and the nonreferring process are then derived based on the postulates. The following implications of these superoperators are found: (1) the change of average photon number due to the one-count process is identical to the well-known Q parameter introduced by Mandel [Opt. Lett. 4, 205 (1979)]; (2) the no-count process is governed by a pseudomaster equation; (3) The probability for the m-count process is the Poisson transform of the initial P function of the cavity radiation; and (4) the nonreferring measurement process is governed by a master equation.The external photodetection of cavity radiation is considered as a continuous quantum measurement in the sense of Srinivas and Davies [Opt. Acta 28, 981 (1981)]. It is analyzed in terms of three elementary processes: the no-leak process, the one-leak-undetected process, and the one-leak-detected process. The first two form a no-count process and the last one, a one-count process. Superoperators for these elementary processes are postulated, following the examples of Srinivas and Davies. The superoperators for the one-count process, the no-count process, the m-count process, and the nonreferring process are then derived based on the postulates. The following implications of these superoperators are found: (1) the change of average photon number due to the one-count process is identical to the well-known Q parameter introduced by Mandel [Opt. Lett. 4, 205 (1979)]; (2) the no-count process is governed by a pseudomaster equation; (3) The probability for the m-count process is the Poisson transform of the initial P function of the cavity radiation; and (4) the nonreferring measurement process is governed by a master equation.

Physical Review AJun 1, 199417 citations

Radiative Transitions

Springer eBooksMar 7, 20070 citations

Experimental prospects for quantum decoherence measurements at colliders

Rafael Aoude, José M. Camacho, Valentin Durupt +6 more

We study the impact of radiation on quantum systems defined by the spins of elementary fermion-antifermion pairs produced at colliders. We present predictions for several processes, showing that energetic final-state radiation can induce decoherence and significantly reduce the entanglement of quantum systems formed by elementary fermion pairs. We investigate the feasibility of observing this effect experimentally in exclusive samples with energetic radiation. A statistically significant signal can be obtained with current data in associated $pp \rightarrow t\bar{t}(g)$ production at the LHC and in $e^+e^- \rightarrow τ^{+}τ^{-}(γ)$ production at Belle 2. Future electron-positron colliders operated at the $Z$ pole or well above the $t\bar{t}$ production threshold will extend these prospects further.We study the impact of radiation on quantum systems defined by the spins of elementary fermion-antifermion pairs produced at colliders. We present predictions for several processes, showing that energetic final-state radiation can induce decoherence and significantly reduce the entanglement of quantum systems formed by elementary fermion pairs. We investigate the feasibility of observing this effect experimentally in exclusive samples with energetic radiation. A statistically significant signal can be obtained with current data in associated $pp \rightarrow t\bar{t}(g)$ production at the LHC and in $e^+e^- \rightarrow τ^{+}τ^{-}(γ)$ production at Belle 2. Future electron-positron colliders operated at the $Z$ pole or well above the $t\bar{t}$ production threshold will extend these prospects further.

arXiv:2604.16268Apr 17, 20260 citations

pp \rightarrow t\bar{t}(g)

production at the LHC and in

e^+e^- \rightarrow τ^{+}τ^{-}(γ)

production at Belle 2. Future electron-positron colliders operated at the

Z

pole or well above the

t\bar{t}

production threshold will extend these prospects further.