Simplified approach to double jumps for fluorescing dipole-dipole interacting atoms

Abstract

A simplified scheme for the investigation of cooperative effects in the quantum jump statistics of small numbers of fluorescing atoms and ions in a trap is presented. It allows the analytic treatment of three dipole-dipole interacting four-level systems which model the relevant level scheme of Ba + ions. For the latter, a huge rate of double and triple jumps was reported in a former experiment and the huge rate was attributed to the dipoledipole interaction. Our theoretical results show that the effect of the dipole-dipole interaction on these rates is at most 5% and that for the parameter values of the experiment there is practically no effect. Consequently it seems that the dipole-dipole interaction can be ruled out as a possible explanation for the huge rates reported in the experiment.

Macroscopic quantum jumps and entangled-state preparation

“…The mean durations of the macroscopic light and dark periods have been calculated using this approach and were found to be in good agreement with experimental findings. Macroscopic quantum jump experiments have also been performed with and analysed for setups containing not only one but several atoms [13,14,15]. In such experiments the number of atoms emitting photons is always discrete, thereby causing random variation between distinct fluorescence levels.…”

Dynamics of atoms in a femtosecond optical dipole trap

“…The physics of cold collisions between atoms in a FORT can be studied experimentally not only by means of the traditionally used analysis of one-and two-atom losses from the trap, but also using spontaneous fluorescence and resonance fluorescence from the atoms in the trap. As was shown in theory and confirmed experimentally, the system of two two-level or multilevel atoms interacting via the DDI is a source of quantum entanglement [47][48][49], as well as a source of cooperative effects in atomic fluorescence, which reveal themselves in the form of macroscopic quantum jumps (light and dark periods), both in ions and atoms [50][51][52]. Moreover, this fluorescence and, therefore, the interaction between the atoms in the trap can be microscopically resolved [53].…”

Lifetime of the 5d2D5/2 level of Ba+Dijck1, Mohanty2, Valappol3 et al. 2018Phys. Rev. A6020View full textAdd to dashboardCite

“…An enhanced rate of multiple jumps (two or more ions shelving or deshelving within the averaging window) was reported in an early experiment with three Ba + ions as an indication of cooperative interactions [53]. However, later calculations [54][55][56] show that the reported enhancement by several orders of magnitude cannot be explained in this way, as the interference effect is limited to deviations of about ±5% from the rates for independent atoms at distances comparable to the wavelength λ = 0.5 µm and quickly becomes negligible when the distance between the ions becomes larger. Superradiance and subradiance at the level of ±1% has been experimentally observed in the 6p 2 P 1/2 to 6s 2 S 1/2 decay rate in a pair of Ba + ions separated by about 1.5 µm [57].…”