Coherence of three-body Förster resonances in Rydberg atoms

Abstract

We have observed recently the Stark-tuned three-body Förster resonances 3 × nP 3/2 (|M |) → nS 1/2 + (n + 1)S 1/2 + nP 3/2 (|M * |) at long-range interactions of a few cold Rb Rydberg atoms [D. B. Tretyakov et al., Phys. Rev. Lett. 119, 173402 (2017)]. The three-body resonance appears at a different dc electric field with respect to the ordinary two-body resonance 2 × nP 3/2 (|M |) → nS 1/2 + (n + 1)S 1/2 and corresponds to a transition when the three interacting atoms change their states simultaneously (two atoms go to the S states, and the third atom remains in the P state but changes its moment projection), with the negligible contribution of the two-body resonance to the population transfer. It thus has a Borromean character and represents an effective three-body operator, which can be used to directly control the three-body interactions in quantum simulations and quantum gates implemented with Rydberg atoms. In this paper we theoretically investigate the coherence of such three-body resonances and we show that high-contrast Rabi-like population oscillations are possible for the localized Rydberg atoms in a certain spatial configuration. This paves the way to implementing three-qubit quantum gates and quantum simulations based on three-body Rydberg interactions.

Two-dimensional spectroscopy of Rydberg gases

“…When going beyond the examples discussed above, using 2D spectroscopy on larger, more theoretically challenging Rydberg systems could also add a window on Rydberg dynamics that is complementary to the many existing techniques, providing new ways to look at dipolar-interacting quantum systems, especially those interacting with their environment [47], involving many-body resonant interactions [48], spin relaxation [49] or transport [50].…”

Time dependence of few-body Förster interactions among ultracold Rydberg atoms

“…More recently, Tretyakov, et al observed the same type of three-body interaction in rubidium Rydberg atoms while conclusively demonstrating the Borromean nature of the energy exchange [24]. Additional work has studied coherence of this interaction and its suitability for use in a quantum gate [25,26].…”

Time Dependence of Few-Body Förster Interactions among Ultracold Rydberg Atoms

“…More recently, Tretyakov et al observed the same type of three-body interaction in rubidium Rydberg atoms while conclusively demonstrating the Borromean nature of the energy exchange [31]. Additional work has studied coherence of this interaction and its suitability for use in a quantum gate [32,33].…”

“…For two atoms at fixed separation, the time dependence should be given by Rabi oscillations; in fact, Ravets et al have observed Rabi oscillations between a pair of Rydberg atoms [20]. A more complicated, but still coherent, oscillation is expected for few-body interactions in a close triplet or quadruplet [33]. However, we have a different amorphous sample of atoms on each shot of our laser, which averages out the oscillations.…”