engleski

Diffuse and triplet satellite bands of KRb molecule

In a hot metal vapor K-Rb mixture usually spectral phenomena of both K2 and Rb2 dimers appear together with KRb bands. Sometimes spectral overlaps preclude a clear observations of the satellite bands in the vicinity of the first resonance lines. However, in the case of potassium-rubidium vapor mixture the resonance lines are located within 765-795 nm spectral region, and the very far blue quasistatic wing can be investigated in detail. We found beside K and Rb satellite bands three distinct satellite bands at 730 nm and a single shoulder at 755.5 nm that we asigned to KRb heteronuclear molecule. The interpretation of these KRb satellite bands in this region is very similar to the interpretation of K2 and Rb2 satellite bands [1] and was presented in a preliminary form in ref. [2]. This will be further discussed in terms of the recent ab initio calculations of the relevant potential curves [3]. Three diffuse bands of KRb peaking at 568.8, 586.3 and 596.4 were found and asigned to the transitions to the (3) and (4) states. Semiclassical spectral simulations were performed with ab initio potentials and approximate transition dipole functions. Quite recently Gabbanini et al. [4] have detected ultracold Rb2 in lowest triplet state by two- photon resonance enhanced ionization at about 600 nm which is the interval of the Rb2 diffuse bands. We believe that resonance enhanced ionization using observed satellite or diffuse bands of KRb can be useful in the detection of ultracold KRb molecules. It is expected that KRb will play an important role in future development of multispecies condensates because the KRb system has very favorable Franck-Condon factors for the photoassociation process [5]. __________________________________________________________ [1] R. Beuc, S. Milosevic, M. Movre, G. Pichler, and D. Veza, FIZIKA (YU) 14 (1982) 345. [2] C. Vadla, R. Beuc, M. Movre and G. Pichler: Satellite bands in KRb mixture, ECAP, Heidelberg 06-10.4.1981. and R. Beuc Master Thesis, University of Zagreb, 1984. ______ [3] S. Rousseau, A.R. Allouche and M. Aubert-Frecon, to be published ______________ [4] C. Gabbanini, A. Fioretti, A. Lucchesini, S. Gozzini and M. Mazzoni, Phys.Rev.Lett. 84 (2000) 2814. _________________________________________________________ [5] H. Wang and W.C. Stwalley, J. Chem. Phys. 108 (1999) 5767

triplet satellite bands; diffuse bands; KRb molecule

nije evidentirano