Buffer-gas loading of atoms and molecules into a magnetic trap

Abstract

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Collisional properties of cold spin-polarized nitrogen gas: Theory, experiment, and prospects as a sympathetic coolant for trapped atoms and molecules

“…A system of close-coupled (CC) equations for the radial functions F M S A M S B m (R) results when the expansion (13) is combined with the Schrödinger equation with Hamiltonian (6). The CC equations are integrated numerically on a radial grid extending from R = 4.0a 0 to R = 50.0a 0 with a constant spacing of 0.04a 0 using the improved log-derivative algorithm [66].…”

“…At present, cold molecular ensembles can be produced by a number of experimental techniques [1,[5][6][7][8][9][10], which can be broadly classified as direct and indirect. The direct techniques are based on removing thermal energy from a pre-existing ensemble of molecules via collisional thermalization or time-dependent electromagnetic fields.…”

“…Due to their large magnetic moments of 3 µ B , the N atoms can be efficiently confined in a magnetic trap using buffer-gas cooling [6]. Previous experimental work [17] has demonstrated that samples of N atoms with densities ∼10 10 -10 11 cm −3 can be routinely produced and held in a magnetic trap for as long as 10 s, allowing for cotrapping of molecular species such as NH [17].…”

Calculations of the binding energies of weakly bound He-He-H, He-He-H-and He-H-H molecules

“…These molecules can exist only in a cold environment and thus are not expected to exist under normal laboratory conditions. With the advent of laser cooling and other cooling methods for atoms and molecules [20][21][22], it may be possible to make observations of these species in the near future.…”

Inelastic Collisions of Ultracold Heteronuclear Molecules in an Optical Trap

“…Ω-doublet, rotational, and vibrational levels, presents a host of new possibilities for precision measurement of fundamental physics [7,8,9,10,11]. Producing ultra-cold samples of polar molecules will facilitate trapping and, thus, the required high densities and long observation times for observing these phenomena.Techniques such as Stark deceleration [12] and buffer gas cooling [13] are capable of producing cold samples from a wide range of molecular species; however, the temperatures and densities currently attainable via these "direct cooling" methods are not sufficient for observing many of the interesting phenomena mentioned above. Conversely, the association of ultra-cold atoms, either via a Feshbach [14] or optical resonance [15], restricts experiments to a limited class of molecules -namely, those composed of laser cooled atoms.…”