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Isolating Free Carbenes, their Mixed Dimers and Organic Radicals
Published on: April 19, 2019
Atom-dimer scattering and long-lived trimers in fermionic mixtures.
J Levinsen1, T G Tiecke, J T M Walraven
1Laboratoire Physique Théorique et Modèles Statistique, Université Paris Sud, CNRS, 91405 Orsay, France.
Physical Review Letters
|November 13, 2009
Summary
We discovered a tunable atom-dimer p-wave resonance in quasi-two-dimensional fermionic mixtures. This finding enables control over interactions, crucial for studying many-body physics with lithium-potassium mixtures.
Area of Science:
- Ultracold atomic physics
- Quantum chemistry
Background:
- Investigating heteronuclear fermionic mixtures near interspecies Feshbach resonances is key to understanding quantum phenomena.
- Controlling interactions in these systems is essential for creating novel quantum states and devices.
Purpose of the Study:
- To explore atom-dimer scattering properties in quasi-two-dimensional (2D) systems.
- To identify and characterize a tunable p-wave resonance in heteronuclear fermionic mixtures.
- To assess the implications for creating and studying weakly bound trimers and many-body systems.
Main Methods:
- Theoretical analysis of atom-dimer scattering in uniform and quasi-2D confined geometries.
- Investigating the influence of confinement frequency on p-wave resonance.
- Analyzing the stability and properties of resulting atom-dimer bound states (trimers).
Main Results:
- A peculiar, tunable atom-dimer p-wave resonance was identified, controllable by confinement frequency.
- This resonance allows switching interactions between attractive and repulsive regimes for K atom and Li-K dimer.
- Weakly bound trimers with unit angular momentum were formed, exhibiting long lifetimes and no enhanced inelastic relaxation.
Conclusions:
- The tunable p-wave resonance provides a powerful mechanism for controlling quantum interactions in ultracold mixtures.
- Lithium-potassium mixtures are excellent candidates for exploring p-wave resonance effects in many-body systems.
- The findings pave the way for future experiments on few-body and many-body physics with controlled p-wave interactions.
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