Observation of Optically Trapped Cold Cesium Molecules

Abstract

We report the first observation of optically trapped cold neutral molecules. Cesium dimers in the electronic ground state are produced directly in a magneto-optical trap and transferred to a dipole trap formed at the focus of a CO 2 laser beam (l 10.6 mm). These neutral molecules were detected using photoionization and time-of-flight spectroscopy. Initial experiments indicate a cold molecule trap lifetime on the order of half a second. [S0031-9007(98)07817-X]

Cavity-enhanced toroidal dipole force traps for dark-field seeking species

“…Molecules have therefore hitherto been trapped only using the red-detuned force of powerful mainframe lasers [8]: with cavity enhancement, they could be confined in less perturbing blue-detuned potentials using only modest laser powers. Indeed, cavity enhancement allows the trapping field to be tuned further from resonance for any species, thus offering lower scattering rates for the same trap depth.…”

“…Despite some residual scattering, such schemes have been used to produce an atomic Bose-Einstein condensate (BEC) [6], to allow the controlled delivery of single atoms [7], and to trap caesium dimers [8].…”

Observation of cold Rb2molecules trapped in an optical dipole trap using a laser-pulse-train technique

“…After their formation, such molecules can be trapped in an optical dipole trap, since the trapping mechanism does not depend on molecular levels. Depending on the temperature, the molecular sample can be either in a thermal regime [2][3][4][5][6] or quantum regime [7][8][9]. Furthermore, they can be either in a single vibrational state [7][8][9] or in a mixture of states [2][3][4][5][6].…”

“…This technique has allowed a great development in the field of cold molecules. So far it has been applied using a single laser pulse for each molecular sample, and therefore it requires the preparation of a new molecular sample for each laser pulse [2][3][4][5][6]11]. In order to obtain reliable data, time-consuming averaging of a larger number of measurements over several different molecular samples is required.…”

“…In both cases, the time evolution of the molecule population allows one to obtain information on atom-molecule and molecule-molecule cold collisions. Therefore, the detection of such molecules is a key factor in all experiments, and it has been done either through the absorption imaging technique [7][8][9][10] or photoionization [2][3][4][5][6]11].…”