The emission spectrum of a pair of two-level atoms coupled by dipole-dipole force in a single-mode radiation field is Studied. It is found that atomic dipole-dipole interaction destroys the symmetry of the spectrum. The spectral properties for the vacuum field and strong field are discussed in detail.
The multiphoton emission spectrum of a pair of coupling two-level atoms interacting with two modes of the radiation field is studied. A general expression for the two-mode multiphoton emission spectrum is presented. The non-degenerate two-photon emission spectra of two atoms are calculated when the two modes of the field are in various number states and some new results are obtained. It is found that the two-atom emission spectrum in the two-mode vacuum field reflects the atomic dipole-dipole interaction more sensitively than in the case of a single-mode vacuum field.
The emission spectrum of a pair of two-level atoms interacting with a single mode of radiation field in an ideal cavity is investigated, where the interaction of each atom with the field may be different. A general expression for the emission spectrum is presented and the spectrum is studied numerically when the radiation field is initially in the vacuum state, pure number state and squeezed-vacuum state, respectively. The effects of the ratio of two coupling constants (R=g 2 /g 1 ) on the emission spectrum are discussed. In contrast with the spectrum of a one-atom system, the spectrum of a two-atom system is much more complicated. Generally, the emission spectrum shows a 12-peak structure for the vacuum state and 16-peak structure for the pure number state. For the squeezed-vacuum state, it is found that the Rabi splitting is most apparent when R=1.
The Raman interaction of a pair of two-level atoms with the radiation field is studied. The emission spectra for two interacting processes are calculated in which either two atoms couple to the field with different constants or with the same constant but at the same time the dipole-dipole interaction between two atoms being included in the consideration. The effect of the relative value of two atom-field coupling constants and also that of atomic dipole-dipo-le interaction on the emission spectra are analyzed.