Topic
Atomic coherence
About: Atomic coherence is a research topic. Over the lifetime, 877 publications have been published within this topic receiving 29395 citations.
Papers published on a yearly basis
Papers
More filters
TL;DR: In this article, a femtosecond pump-probe spectroscopy was used to investigate the dynamics of superfluid helium droplets with potassium atoms to form complexes in which the metal atom is weakly bound to the cluster surface.
Abstract: Superfluid helium droplets are doped with potassium atoms to form complexes in which the metal atom is weakly bound to the cluster surface. The dynamics of these systems upon electronic excitation of the metal atom is probed by means of femtosecond pump-probe spectroscopy. Alignment of the excited potassium $p$ orbital parallel to the cluster surface leads to quantum interferences, the decay of which gives information on the ultrafast perturbation of the induced atomic coherence by the superfluid environment; exciting the $p$ state aligned perpendicularly, the strong repulsive interaction with the helium surface comes into play and the response of the helium environment is followed in time.
41 citations
TL;DR: In this article, the authors derive from first principles the dynamical equations for the interaction between a heat bath and a multilevel atom with some near degenerate states, and address the question whether such equations lead to a steady state that is consistent with the thermodynamic equilibrium.
Abstract: We derive from first principles the dynamical equations for the interaction between a heat bath and a multilevel atom with some near degenerate states. Such dynamical equations exhibit atomic coherence terms which arise from the interference of transition amplitudes. We address the question whether such equations lead to a steady state that is consistent with the thermodynamic equilibrium. We show that coherence affects the dynamics of the system, but the equilibrium conditions are still characterized by Boltzmann factors. We also show how an asymmetric treatment of spontaneous and stimulated processes could lead to a steady state which is at variance with the principles of thermodynamic equilibrium. We show that such a steady state can be realized by pumping with broadband laser fields. Finally, we show that coherences in the dynamical equations can be probed via the spectrum of fluorescence.
41 citations
TL;DR: In this paper, spontaneous emission can create coherence in a ladder-type three-level atom with equispaced levels, subject to the condition that the atomic dipole moments are nonorthogonal.
41 citations
TL;DR: In this article, an ellipticity-dependent nonlinear magneto-optic rotation of elliptically polarized light propagating in a medium with atomic coherence was shown to be associated with an enhancement of Kerr and higher-order nonlinearities accompanied by suppression of the other linear and nonlinear susceptibility terms.
Abstract: We predict theoretically and demonstrate experimentally an ellipticity-dependent nonlinear magneto-optic rotation of elliptically polarized light propagating in a medium with atomic coherence. We show that this effect results from hexadecapole and higher-order moments of the atomic coherence, and is associated with an enhancement of Kerr and higher-order nonlinearities accompanied by suppression of the other linear and nonlinear susceptibility terms of the medium. These nonlinearities might be useful for quantum signal processing. In particular, we report an observation of enhancement of the polarization rotation of elliptically polarized light resonant with the ${5S}_{1/2}F=\stackrel{\ensuremath{\rightarrow}}{2}{5P}_{1/2}F=1$ transition of ${}^{87}\mathrm{Rb}.$
41 citations
TL;DR: This work experimentally demonstrates the vortex solitons of four-wave mixing (FWM) in multi-level atomic media created by the interference patterns with superposing three or more waves.
Abstract: We experimentally demonstrate the vortex solitons of four-wave mixing (FWM) in multi-level atomic media created by the interference patterns with superposing three or more waves. The modulation effect of the vortex solitons is induced by the cross-Kerr nonlinear dispersion due to atomic coherence in the multi-level atomic system. These FWM vortex patterns are explained via the three-, four- and five-wave interference topologies.
40 citations