Spectroscopy Interference Research Articles

Spectroscopy of systems of two identical atoms: effects of quantum interference

Several effects of quantum interference in spectroscopy of a system of two atoms are discussed. (i) In the system of spatially separated atoms in a one-dimensional (1D) geometry (a single-mode waveguide or photon crystal), a (meta)stable excited entangled state can be formed, its decay being very sensitive to the distance between the atoms and to perturbations which cause a difference between their resonance frequencies. (ii) In a system of closely located atoms in 3D space, the extreme sensitivity of absorption and fluorescence spectra to the direction of the applied magnetic field is demonstrated. These theoretical predictions can be useful for the quantum information processing and ultrasensitive measurements.

Three-photon interference: Spectroscopy of linear and nonlinear media

The nonlinear interference accompanying three-photon spontaneous parametric light scattering is considered. The frequency-angle line shape of the scattering is calculated for nonlinear-crystal/ linear-dispersive-medium/nonlinear-crystal and nonlinear-crystal/nonlinear-crystal systems. The question of the possible use of nonlinear interference in spectroscopy is discussed.