Spectroscopy of photoassociation of collisional pairs of mercury atoms: Determination of parameters of molecular terms

James Gary Eden, Henry Tran, V. S. Zuev

Marcin Bober, Mateusz Borkowski, Piotr Morzyński +4 more

We report on a photoassociation approach to determine the scattering lengths for1So-3Po and3Po-3Po cold collisions. Positions of molecular states, connected with asymptotes of1So+3S1 and3Po+3S1 states could be determined using a tunable 679 nm laser and atoms trapped in an optical lattice. This approach allows an indirect calculation (without direct probing of1S0-3P0 molecular state) of the effect of cold collisions on an optical atomic clock operation. We also propose to realize a molecular clock with bosonic ytterbium molecules.

Mateusz Borkowski, Piotr Morzyński, R. Ciuryło +5 more

Photoassociation spectroscopy, based on forming of molecules from colliding atoms in the presence of light, is a priceless tool for the study of atomic interactions. It enables direct measurements of bound state energies, both in excited and ground state molecules. Applications include determinations of s -wave scattering lengths, as well as atomic state lifetimes. In this work we present the results of our research on the mass-scaling behaviour of molecular bound state energies and collisional properties in spin-singlet atoms. We will concentrate on two such species: strontium and ytterbium, both of which offer several stable isotopes, enabling mass tuning of the system's properties.

T. H. Bergeman

K. M. Jones, Eite Tiesinga, Paul D. Lett +1 more

Photoassociation is the process in which two colliding atoms absorb a photon to form an excited molecule. The development of laser-cooling techniques for producing gases at ultracold $(<1\phantom{\rule{0.3em}{0ex}}\mathrm{mK})$ temperatures allows photoassociation spectroscopy to be performed with very high spectral resolution. Of particular interest is the investigation of molecular states whose properties can be related, with high precision, to the properties of their constituent atoms with the ``complications'' of chemical binding accounted for by a few parameters. These include bound long-range or purely long-range vibrational states in which two atoms spend most or all of their time at large internuclear separations. Low-energy atomic scattering states also share this characteristic. Photoassociation techniques have made important contributions to the study of all of these. This review describes what is special about photoassociation spectroscopy at ultracold temperatures, how it is performed, and a sampling of results including the determination of scattering lengths, their control via optical Feshbach resonances, precision determinations of atomic lifetimes from molecular spectra, limits on photoassociation rates in a Bose-Einstein condensate, and briefly, production of cold molecules. Discussions are illustrated with examples on alkali-metal atoms as well as other species. Progress in the field is already past the point where this review can be exhaustive, but an introduction is provided on the capabilities of photoassociation spectroscopy and the techniques presently in use.

V. K. Bykhovskii, E. E. Nikitin