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Observation of vibrational overtones by single-molecule resonant photodissociation.

ABSTRACT: Molecular ions can be held in a chain of laser-cooled atomic ions by sympathetic cooling. This system is ideal for performing high-precision molecular spectroscopy with applications in astrochemistry and fundamental physics. Here we show that this same system can be coupled with a broadband laser to discover new molecular transitions. We use three-ion chains of Ca(+) and CaH(+) to observe vibrational transitions via resonance-enhanced multiphoton dissociation detected by Ca(+) fluorescence. On the basis of theoretical calculations, we assign the observed peaks to the transition from the ground vibrational state, ν=0 to ν=9 and 10. Our method allows us to track single-molecular events, and it can be extended to work with any molecule by using normal mode frequency shifts to detect the dissociation. This survey spectroscopy serves as a bridge to the precision spectroscopy required for molecular ion control.

SUBMITTER: Khanyile NB

PROVIDER: S-EPMC4525170 | biostudies-other | 2015

REPOSITORIES: biostudies-other

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