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arXiv:1406.0477

Analyzing Feshbach resonances -- A $^6$Li -$^{133}$Cs case study

R. Pires, Repp, Marc, Juris Ulmanis, E. D. Kuhnle, Matthias Weidemüller, Tiecke, Tobias G., Chris H. Greene, Brandon Ruzic, John L. Bohn, E. Tiemann

Published Jun 2, 2014• 3 citations
arXivHTMLPDF

Abstract

We provide a comprehensive comparison of a coupled channels calculation, the asymptotic bound state model (ABM), and the multichannel quantum defect theory (MQDT). Quantitative results for $^6$Li -$^{133}$Cs are presented and compared to previously measured $^6$Li -$^{133}$Cs Feshbach resonances (FRs) [M. Repp et al., Phys. Rev. A 87 010701(R) (2013)]. We demonstrate how the accuracy of the ABM can be stepwise improved by including magnetic dipole-dipole interactions and coupling to a non-dominant virtual state. We present a MQDT calculation, where magnetic dipole-dipole and second order spin-orbit interactions are included. A frame transformation formalism is introduced, which allows the assignment of measured FRs with only three parameters. All three models achieve a total rms error of < 1G on the observed FRs. We critically compare the different models in view of the accuracy for the description of FRs and the required input parameters for the calculations.

DOI
10.48550/arxiv.1406.0477

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