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arXiv:1412.4295 · New Journal of Physics

Quantum defect theory description of weakly bound levels and Feshbach resonances in LiRb

Jesús Pérez‐Ríos, Sourav Dutta, Yong P Chen, Chris H. Greene

Published Apr 27, 2015• 7 citations
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Abstract

The multichannel quantum defect theory (MQDT) in combination with the frame transformation (FT) approach is applied to model the Fano–Feshbach resonances measured for 7 Li 87 Rb and 6 Li 87 Rb Marzok et al (2009 Phys. Rev. A 79 012717 ). The MQDT results show a level of accuracy comparable to that of previous models based on direct, fully numerical solutions of the the coupled channel Schrödinger equations. Here, energy levels deduced from 2-photon photoassociation (PA) spectra for 7 Li 85 Rb are assigned by applying the MQDT approach, obtaining the bound state energies for the coupled channel problem. Our results confirm that MQDT yields a compact description of PA observables as well as the Fano–Feshbach resonance positions and widths.

DOI
10.1088/1367-2630/17/4/045021

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