Ryan Carollo

Resonant coupling in the heteronuclear alkali dimers for direct photoassociative formation of X(0,0) ultracold molecules.

Promising pathways for photoassociative formation of ultracold heteronuclear alkali metal dimers in their lowest rovibronic levels (denoted X(0,0)) are examined using high-quality ab initio calculations of potential energy curves currently available. A promising pathway for KRb, involving the resonant coupling of the 2(1)Pi and 1(1)Pi states just below the lowest excited asymptote (K(4s) + Rb(5p(1/2))), is found to occur also for RbCs and less promisingly for KCs also. The resonant coupling of the 3(1)Sigma(+) and 1(1)Pi states, also just below the lowest excited asymptote, is found to be promising for LiNa, LiK, and LiRb and less promising for LiCs and KCs. Direct photoassociation to the 1(1)Pi state near dissociation appears promising in the final dimers NaK, NaRb, and NaCs, although detuning more than 100 cm(-1) below the lowest excited asymptote may be required.

Shortcuts for understanding rovibronic spectroscopy of ultracold alkali metal diatomic molecules

The high-resolution rovibronic spectroscopies of cold and ultracold molecules (e.g. supersonic molecular beam excitation spectra (MB), photoassociation spectra of ultracold atoms (PA), resonance-enhanced multiphoton ionization spectra (REMPI), stimulated Raman transfer (SRT) spectra) are of major current interest. This manuscript summarizes the significant level of understanding of these various spectroscopies, enabled by using simple graphical and semiclassical ideas and shortcuts. Physical realizations of these spectroscopies will be illustrated using the alkali metal diatomic molecules, both homonuclear (e.g. Rb2) and heteronuclear (e.g. KRb).

Upper Bound to the Ionization Energy of 85 Rb2

’s, such asthe extrapolation of a Rydberg series or the observationof the onset of direct photoionization or autoionization(Ref. [15] contains examples of each of these methods).These methods rely on two distinct ionization mecha-nisms, directphotoionizationandautoionization[19]. Di-rect photoionization, or photoionization for short, pro-ceeds through a single step,Rb