Quantum 2025 – scientific programme

Parts | Days | Selection | Search | Updates | Downloads | Help

TUE: Tuesday Contributed Sessions

TUE 8: Correlated Quantum Matter: Contributed Session to Symposium I

TUE 8.4: Talk

Tuesday, September 9, 2025, 15:00–15:15, ZHG009

Modelling of collisional spin entanglement beyond the Born-Markov approximation — •Robert Weiß¹, Scott Parkins^2,3, Mikkel F. Andersen^3,4, and Sandro Wimberger^5,6 — ¹Institut für theoretische Physik, Universität Heidelberg — ²Department of Physics, University of Auckland — ³Dodd-Walls Centre for Photonic and Quantum Technologies — ⁴Department of Physics, University of Otago — ⁵Department of Mathematical, Physical and Computer Sciences, Parma University — ⁶INFN, Sezione Milano-Bicocca, Parma group

It was shown experimentally that colliding cold atoms produce entanglement between their spin states [1]. A thorough theoretical foundation and prediction was restricted in modelling the internal and external atomic degrees of freedom due to computational constraints. We demonstrate why established analytical techniques restricting to the spins only and relying on the Born-Markov approximation fail to reproduce the experimental results. The Markov approximation is not applicable because the correlations in the motional degree of freedom do not decay on a short enough time scale. The Born approximation is questionable as the interatomic interaction is too strong. Numerical models are presented which capture the observed dynamics well including non-Markovian effects and the relative motion.

[1] P. Sompet et. al., Nat. Comm. 10, 1889 (2019)

Keywords: entanglement generation; cold-atom collisions; non-Markovian evolution