相关论文: Collisional trap losses of cold, magnetically-trap…
We present measurements and calculations of the trap loss rate for laser cooled Rb atoms confined in either a magneto-optic or a magnetic quadrupole trap when exposed to a room temperature background gas of Ar. We study the loss rate as a…
We study inelastic collisions between CaF molecules and $^{87}$Rb atoms in a dual-species magneto-optical trap. The presence of atoms increases the loss rate of molecules from the trap. By measuring the loss rates and density distributions,…
Magnetic trapping of bromine atoms at temperatures in the milliKelvin regime is demonstrated for the first time. The atoms are produced by photodissociation of Br$_2$ molecules in a molecular beam. The lab-frame velocity of Br atoms is…
Collisions with background atoms are known to induce a significant shift in the frequency of state-of-the-art optical atomic clocks and contribute to state decoherence in cold atom experiments. The effects of these collisions can be…
We report the measurement of collision rate coefficient for collisions between ultracold Cs atoms and low energy Cs+ ions. The experiments are performed in a hybrid trap consisting of a magneto-optical trap (MOT) for Cs atoms and a Paul…
We present measurements of thermalized collisional rate coefficients for ultra-cold $^7$Li and $^{87}$Rb colliding with room-temperature He, Ne, N$_2$, Ar, Kr, and Xe. In our experiments, a combined flowmeter and dynamic expansion system, a…
We studied light assisted collisions of Tm atoms in a magneto optical trap (MOT) for the first time, working on a weak cooling transition at 530.7 nm $(4f^{13}(^2F^0)6s^2,J=7/2,F=4$ to $4f^{12}(^3H_6)5d_{5/2}6s^2,J=9/2,F=5)$. We observed a…
We have studied hetero- and homonuclear excited state/ground state collisions by loading both $^{85}$Rb and $^{87}$Rb into a far off resonant trap (FORT). Because of the relatively weak confinement of the FORT, we expect the hyperfine…
We report on trapping of fermionic 40K atoms in a red-detuned standing-wave optical trap, loaded from a magneto-optical trap. Typically, 10^6 atoms are loaded at a density of 10^12 cm^-3 and a temperature of 65 microK, and trapped for more…
We calculate the rates of inelastic collisions for ultracold alkali-metal atoms in radiofrequency-dressed traps, using coupled-channel scattering calculations on accurate potential energy surfaces. We identify an rf-induced loss mechanism…
We realize a combined trap for bosonic chromium 52Cr and rubidium 87Rb atoms. First experiments focus on exploring a suitable loading scheme for the combined trap and on studies of new trap loss mechanisms originating from simultaneous…
We study the properties of a Rb magneto-optic trap loaded from a commercial getter source which provides a large flux of atoms for the trap along with the capability of rapid turn-off necessary for obtaining long trap lifetimes. We have…
We present an experimental and theoretical study of atom-molecule collisions in a mixture of cold, trapped atomic nitrogen and NH molecules at a temperature of $\sim 600$~mK. We measure a small N+NH trap loss rate coefficient of…
In this article, we report the measurement of collision-induced loss rate coefficients \beta_{Li,Rb} and \beta_{Rb,Li}, and also discuss means to significantly suppress such collision induced losses. We first describe our dual-species…
We have trapped cesium atoms over many minutes in the focus of a CO$_2$-laser beam employing an extremely simple laser system. Collisional properties of the unpolarized atoms in their electronic ground state are investigated. Inelastic…
Collision cross sections and rate constants between two ground- state oxygen molecules are investigated theoretically at translational energies below $\sim 1$K and in zero magnetic field. We present calculations for elastic and spin-…
We investigate collisional properties of lithium and cesium which are simultaneously confined in a combined magneto-optical trap. Trap-loss collisions between the two species are comprehensively studied. Different inelastic collision…
We measure the collision rate coefficient between laser cooled Rubidium (Rb) atoms in a magneto-optical trap (MOT) and optically dark Rb+ ions in an overlapping Paul trap. In such a mixture, the ions are created from the MOT atoms and…
Using GRB radio afterglow observations, we calculate the fraction of shocked plasma energy in the magnetic field in relativistic collisionless shocks ($\epsilon_B$). We obtained $\epsilon_B$ for 38 bursts by assuming that the radio…
We study light-assisted collisions in an ensemble containing a small number (~3) of cold Rb87 atoms trapped in a microscopic dipole trap. Using our ability to operate with one atom exactly in the trap, we measure the one-body heating rate…