Stimulated Emission Studies of Ultracold Rydberg Atoms

Population dynamics in weakly excited clouds of ultracold $^{87}\text{R}\text{b}$ Rydberg atoms were studied by means of trap loss, fluorescence detection, and state-dependent stimulated emission. Rydberg atoms were excited to various $nl$ Rydberg states via continuous two-photon excitation from a magneto-optical trap. A stimulated emission probe laser was then used to bring the Rydberg atoms down to the $6{P}_{3/2}$ state, allowing state-dependent detection of the Rydberg atoms. Measurements of trap loss and fluorescent emission reveal information about the evolution of the Rydberg populations. In particular, population in the initial Rydberg state quickly transfers to other Rydberg states by a noncollisional mechanism, likely superradiant emission. The trap-loss measurements are consistent with black-body ionization as the dominant loss mechanism.Population dynamics in weakly excited clouds of ultracold $^{87}\text{R}\text{b}$ Rydberg atoms were studied by means of trap loss, fluorescence detection, and state-dependent stimulated emission. Rydberg atoms were excited to various $nl$ Rydberg states via continuous two-photon excitation from a magneto-optical trap. A stimulated emission probe laser was then used to bring the Rydberg atoms down to the $6{P}_{3/2}$ state, allowing state-dependent detection of the Rydberg atoms. Measurements of trap loss and fluorescent emission reveal information about the evolution of the Rydberg populations. In particular, population in the initial Rydberg state quickly transfers to other Rydberg states by a noncollisional mechanism, likely superradiant emission. The trap-loss measurements are consistent with black-body ionization as the dominant loss mechanism.

arXiv:0803.1132Physical Review AMay 23, 200847 citations

Experiments with an Ultracold Gas of Rydberg atoms

J. Denskat, M. Reetz‐Lamour, Thomas Amthor +4 more

Jan 1, 20060 citations

Ultracold Rydberg Atom–Atom Interaction

H. R. Sadeghpour

Springer handbooksJan 1, 20230 citations

Alignment probing of Rydberg states by stimulated emission

Eileen M. Spain, Mark J. Dalberth, Paul D. Kleiber +3 more

The possibility of probing the collisions of aligned Rydberg atoms by stimulated emission is assessed with studies of a polarized state and a new measurement of a collisional alignment effect in atomic Ca. The stimulated emission method uses a laser to dump the desired state to a lower level which subsequently fluoresces. The technique can be used to obtain populations and polarization dependent information. First, the method is tested by applying it to an aligned Ca(4s17d 1D2) state. Alignment curves are measured when the initial state is prepared with both parallel and perpendicular relative polarizations. The experimentally observed alignment compares well with that derived from theoretical considerations of a saturated stimulated transition. Second, a two-vector collisional alignment experiment (initial state and relative velocity vector) is performed to study the energy transfer process Ca(4s7d 1D2)+He→Ca(4s6f 1F3)+He+ΔE=17.7 cm−1, and alignment effects are measured by both stimulated emission and conventional direct fluorescence detection. A preference for the ‖m‖=1 and 2 initial states is observed in the relative cross sections. Essentially identical data are obtained with the two detection methods when elliptically polarized light is used for the stimulated emission detection method. The stimulated emission technique can provide alignment and population information of the final states, making it an excellent new tool for both three-vector correlation experiments and state-to-state Rydberg transitions.The possibility of probing the collisions of aligned Rydberg atoms by stimulated emission is assessed with studies of a polarized state and a new measurement of a collisional alignment effect in atomic Ca. The stimulated emission method uses a laser to dump the desired state to a lower level which subsequently fluoresces. The technique can be used to obtain populations and polarization dependent information. First, the method is tested by applying it to an aligned Ca(4s17d 1D2) state. Alignment curves are measured when the initial state is prepared with both parallel and perpendicular relative polarizations. The experimentally observed alignment compares well with that derived from theoretical considerations of a saturated stimulated transition. Second, a two-vector collisional alignment experiment (initial state and relative velocity vector) is performed to study the energy transfer process Ca(4s7d 1D2)+He→Ca(4s6f 1F3)+He+ΔE=17.7 cm−1, and alignment effects are measured by both stimulated emission and conventional direct fluorescence detection. A preference for the ‖m‖=1 and 2 initial states is observed in the relative cross sections. Essentially identical data are obtained with the two detection methods when elliptically polarized light is used for the stimulated emission detection method. The stimulated emission technique can provide alignment and population information of the final states, making it an excellent new tool for both three-vector correlation experiments and state-to-state Rydberg transitions.

The Journal of Chemical PhysicsJun 22, 19959 citations

Formation of ultracold ion pairs through long-range Rydberg molecules

Michael Peper, Johannes Deiglmayr

Abstract We propose a new approach to excite ion-pair states of ultracold dimers. The central idea is a two-step process where first long-range Rydberg molecules are formed by photoassociation, which are then driven by stimulated emission towards the ion-pair state, a process bearing features of a photo-induced harpooning reaction. We assess the feasibility of this approach through a detailed experimental and theoretical study on a specific system, p-wave-scattering dominated long-range Rydberg molecules in caesium, and discuss potential applications for the study of strongly correlated plasmas consisting of oppositely charged particles of equal or similar mass.Abstract We propose a new approach to excite ion-pair states of ultracold dimers. The central idea is a two-step process where first long-range Rydberg molecules are formed by photoassociation, which are then driven by stimulated emission towards the ion-pair state, a process bearing features of a photo-induced harpooning reaction. We assess the feasibility of this approach through a detailed experimental and theoretical study on a specific system, p-wave-scattering dominated long-range Rydberg molecules in caesium, and discuss potential applications for the study of strongly correlated plasmas consisting of oppositely charged particles of equal or similar mass.

arXiv:2001.11754Journal of Physics B Atomic Molecular and Optical PhysicsFeb 14, 202015 citations

Population dynamics in weakly excited clouds of ultracold

^{87}\text{R}\text{b}

Rydberg atoms were studied by means of trap loss, fluorescence detection, and state-dependent stimulated emission. Rydberg atoms were excited to various

nl

Rydberg states via continuous two-photon excitation from a magneto-optical trap. A stimulated emission probe laser was then used to bring the Rydberg atoms down to the

6{P}_{3/2}

state, allowing state-dependent detection of the Rydberg atoms. Measurements of trap loss and fluorescent emission reveal information about the evolution of the Rydberg populations. In particular, population in the initial Rydberg state quickly transfers to other Rydberg states by a noncollisional mechanism, likely superradiant emission. The trap-loss measurements are consistent with black-body ionization as the dominant loss mechanism.