Trap loss in a metastable helium-rubidium magneto-optical trap

Abstract

We present results of the study of a simultaneously confined metastable helium (He * ) and rubidium magnetooptical trap (MOT). By monitoring the trap decay of the 87 Rb MOT with and without a He * MOT present, we find the light-assisted, two-body loss rate to be β Rb-He * = (6 ± 2) × 10 −10 cm 3 /s. Moreover, we find that it is possible to create a large, robust 87 Rb-He * MOT, opening the possibility of creating a 87 Rb-He * Bose-Einstein condensate. This would be the first dual-species condensate incorporating an alkali metal ground-state atom and an excited-state noble gas atom.

Collisional loss of cesium Rydberg atoms in a magneto-optical trap

“…We can estimate α = 9302 s −1 as the sum of the spontaneous radiation and blackbody radiation rates by Eqs. (5) and (6), and corresponding fitting coefficients are taken from Ref. [23].…”

“…In contrast to thermal atomic experiments, collisions between cold atoms offer many interesting features connected with their low collision energy and long collision duration. Collisions become very sensitive to long-range interactions and to the absorption and emission of radiation during the collision time [3], e.g., collision loss in singlespecies [4] or two-species [5] magneto-optical-trap systems, and atom-molecule and molecule-molecule collisions [6]. In additional, the ultracold Rydberg atoms have been extensively investigated in many-body collisions [7,8], state mixing [9,10], lifetime measurements [11], and spontaneous evolution into ultracold plasmas [12].…”

Long-range interactions between excited helium and alkali-metal atoms

“…Most dual-species experiments involve combinations of alkali-metal atoms, such as Na-{K, Rb, Cs} [9], K-{Rb, Cs} [2,6,9], and Rb-Cs [9,10]. Recently, a few experiments have employed ultracold mixtures of alkalimetal and metastable noble gas atoms, such as 40 Ar * -87 Rb [11,12] and He * -87 Rb [12][13][14]. The latter mixture is promising for creating a dual-species Bose-Einstein condensate by significantly suppressing the Penning ionization [13][14][15], which causes the trap losses.…”

An ultracold, optically trapped mixture of 87Rb and metastable 4He atoms

“…Our experiment involves an ultracold mixture of 4 He * + 87 Rb, for which dual-species laser-cooling and trapping was first achieved by Byron et al [55]. Magnetic trapping of the stable, doubly spin-stretched spin-state combination |m s = +1 4 He * + |f = 2, m f = +2 87 Rb (see Fig.…”