arXiv subjects

E. G. M. Van Kempen

Publications and source records attributed to E. G. M. Van Kempen.

3 recordsLinked to original sources

arXiv2005

Resonant scattering properties close to a p-wave Feshbach resonance

We present a semi-analytical treatment of both the elastic and inelastic collisional properties near a p-wave Feshbach resonance. Our model is based on a simple three channel system that reproduces more elaborate coupled-channel calculations. We stress the main differences between s-wave and p-wave scattering. We show in particular that, for elastic and inelastic scattering close to a p-wave Feshbach resonance, resonant processes dominate over the low-energy behaviour.

cond-mat.mes-hall↗

arXiv2004

Expansion of a lithium gas in the BEC-BCS crossover

We report on experiments in $^6$Li Fermi gases near Feshbach resonances. A broad s-wave resonance is used to form a Bose-Einstein condensate of weakly bound $^6$Li$_2$ molecules in a crossed optical trap. The measured molecule-molecule scattering length of $170^{+100}_{-60}$ nm at 770 G is found in good agreement with theory. The expansion energy of the cloud in the BEC-BCS crossover region is measured. Finally we discuss the properties of p-wave Feshbach resonances observed near 200 Gauss and new s-wave resonances in the heteronuclear $^6$Li- $^7$Li mixture.

cond-mat.stat-mech↗

arXiv2004

P-wave Feshbach resonances of ultra-cold $^6$Li

We report the observation of three p-wave Feshbach resonances of $^6$Li atoms in the lowest hyperfine state $f=1/2$. The positions of the resonances are in good agreement with theory. We study the lifetime of the cloud in the vicinity of the Feshbach resonances and show that depending on the spin states, 2- or 3-body mechanisms are at play. In the case of dipolar losses, we observe a non-trivial temperature dependence that is well explained by a simple model.

quant-ph↗