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Cheng Chin

Publications and source records attributed to Cheng Chin.

74 records · Page 5Linked to original sources

Thermal equilibrium and efficient evaporation of an ultracold atom-molecule mixture

We derive the equilibrium conditions for a thermal atom-molecule mixture near a Feshbach resonance. Under the assumption of low collisional loss, thermodynamical properties are calculated and compared to the measurements of a recent experiment on fermionic lithium experiment. We discuss and evaluate possible collision mechanisms which can lead to atom-molecule conversion. Finally, we propose a novel evaporative cooling scheme to efficiently cool the molecules toward Bose-Einstein condensation.

cond-mat.soft↗

Sensitive Detection of Cold Cesium Molecules by Radiative Feshbach Spectroscopy

We observe the dynamic formation of $Cs_2$ molecules near Feshbach resonances in a cold sample of atomic cesium using an external probe beam. This method is 300 times more sensitive than previous atomic collision rate methods, and allows us to detect more than 20 weakly-coupled molecular states, with collisional formation cross sections as small as $σ=3\times 10^{-16}$cm$^2$. We propose a model to describe the atom-molecule coupling, and estimate that more than $2 \times 10^5$ $Cs_2$ molecules coexist in dynamical equilibrium with $10^8$ $Cs$ atoms in our trap for several seconds.

cond-mat↗