We present a state-of-the-art reanalysis of experimental results on Efimov resonances in the three-fermion system of Li6. We discuss different definitions of the three-body parameter (3BP) for Efimov states and adopt a definition that excludes effects due to deviations from universal scaling for low-lying states. We develop a finite-temperature model for the case of three distinguishable fermions and apply it to the excited-state Efimov resonance to obtain the most accurate determination to date of the 3BP in an atomic three-body system. Our analysis of ground-state Efimov resonances in the same system yields values for the three-body parameter that are consistent with the excited-state result. Recent work has suggested that the reduced 3BP for atomic systems is a near-universal quantity, almost independent of the particular atom involved. However, the value of the 3BP obtained for Li6 is significantly (∼20%) different from that previously obtained from the excited-state resonance in Cs. The difference between these values poses a challenge for theory.
|Original language||English (US)|
|Journal||Physical Review A - Atomic, Molecular, and Optical Physics|
|State||Published - Oct 30 2014|
All Science Journal Classification (ASJC) codes
- Atomic and Molecular Physics, and Optics