Physica Scripta

Collisional dynamics of a few atom quantum system with tunable interaction

Neha Singh, Ruhanshi Barad, Shweta, Kamalkant, Aditya Choudhary, Prosenjit Majumder, Bodhaditya Santra

Published May 19, 2023• 2 citations

Abstract

Abstract The advent of single-atom trapping in optical tweezers and experimental evolution in control, isolation, and manipulation of cold atoms allows us to manifest the few-body physics and its connection with the many-body systems. In cold atom experiments, the universality of few-body physics is majorly governed by the scattering length which makes it an important parameter in determining theoretically calculated loss rates. Here, we numerically study the 3-body collisional dynamics for Cesium atoms using the atom loss model described by Born-Markov approximation. Using the Cs atoms provides us the freedom to vary the scattering length, a , as a function of the magnetic field through Feshbach resonances. We investigate the three-, two-, and one-particle processes in the repulsive interactions regime at different values for a . We find that the probability of one atom remaining in the trap is maximum at B = 26 G corresponding to a = 402.382 a 0 and has the highest value amongst the probability of zero-, two-, and three-particle remaining in the trap at same magnetic field after the collision. Our findings leads to high fidelity single atom tweezers which have direct application in creating defect free arrays for quantum information processing purposes.

DOI: 10.1088/1402-4896/acd72a

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