Related papers: Molecular states near a collision threshold
Elastic scattering resonances occurring in ultracold collisions of either bosonic or fermionic polar molecules are investigated. The Born-Oppenheimer adiabatic representation of the two-bodydynamics provides both a qualitative…
This work investigates how the closed channel of a Feshbach resonance is characterised by experimental observables. Surprisingly, it is found that the two-body observables associated with the Feshbach resonance can be insensitive to the…
We calculate and analyze Feshbach resonance spectra for ultracold Yb($^1$S$_0$) + Yb($^3$P$_2$) collisions as a function of an interatomic potential scaling factor $\lambda$ and external magnetic field. We show that, at zero field, the…
We study the behavior of the Eisenbud-Wigner collisional time delay around Feshbach resonances in cold and ultracold atomic and molecular collisions. We carry out coupled-channels scattering calculations on ultracold Rb and Cs collisions.…
A rigorous quantum theory of atomic collisions in the presence of radio frequency (rf) magnetic fields is developed and applied to elucidate the effects of combined dc and rf magnetic fields on elastic scattering in ultracold collisions of…
Feshbach resonances in ultracold collisions often result from an interplay between many collision channels. Simple two-channel models can be introduced to capture the basic features, but cannot fully reproduce the situation when several…
$N$-body non efimovian bound or quasi-bound states for particles with short range interactions are considered in arbitrary dimensions. The different resonance regimes near the threshold are depicted by using a generalization of the…
We have measured a p-wave Feshbach resonance in a single-component, ultracold Fermi gas of potassium atoms. We have used this resonance to enhance the normally suppressed p-wave collision cross-section to values larger than the background…
We have investigated magnetically tunable Feshbach resonances arising from the interaction of Li($^2S$) with metastable Yb($^3P_2$) and ($^3P_0$). For Yb($^3P_2$), all the resonance features are strongly suppressed by inelastic collisions…
We derive the equilibrium conditions for a thermal atom-molecule mixture near a Feshbach resonance. Under the assumption of low collisional loss, thermodynamical properties are calculated and compared to the measurements of a recent…
A novel atom-molecule conversion technique has been investigated. Ultracold 85Rb atoms sitting in a DC magnetic field near the 155G Feshbach resonance are associated by applying a small sinusoidal oscillation to the magnetic field. There is…
The electronic structure of the (LiYb)$^+$ molecular ion is investigated with two variants of the coupled cluster method restricted to single, double, and noniterative or linear triple excitations. Potential energy curves for the ground and…
We show that the probability of the collision-induced absorption of non-resonant microwave photons by a gas of ultracold molecules is dramatically enhanced near a Feshbach scattering resonance. This can be used for detecting Feshbach…
Here we present a four-channel model that incorporates a magnetically tunable Feshbach resonance in a system of three atoms that interact via pairwise van der Waals interactions. Our method is designed to model recent experiments where the…
Multichannel quantum defect theory (MQDT) provides a powerful toolkit for describing and understanding collisions of cold alkali atoms. Various MQDT approximations differ primarily in how they characterize the so-called short-ranged…
We observe the dynamic formation of $Cs_2$ molecules near Feshbach resonances in a cold sample of atomic cesium using an external probe beam. This method is 300 times more sensitive than previous atomic collision rate methods, and allows us…
Starting from a multichannel quantum-defect theory, we derive analytic descriptions of a magnetic Feshbach resonance in an arbitrary partial wave $l$, and the atomic interactions around it. An analytic formula, applicable to both broad and…
Ultracold molecules offer brand new opportunities to probe the variation of fundamental constants with unprecedented sensitivity. This paper summarizes theoretical background and current constraints on the variation of fine structure…
High partial-wave ($l\ge2$) Feshbach resonance (FR) in an ultracold mixture of $^{85}$Rb-$^{87}$Rb atoms is investigated experimentally aided by a partial-wave insensitive analytic multichannel quantum-defect theory (MQDT). Two "broad"…
We present a simple one-dimensional example of a spin 1/2 particle submitted to a delta-type potential which interacs differently with the two components of the wavefunction and to an external magnetic field. It has two coupled channels,…