Discrete–Discrete and Continuous–Continuous Variable Entanglement Generated in Molecular Collisions

Entanglement emerges naturally from quantum dynamics of interacting molecular systems and plays a central role in quantum technologies such as computation, sensing, and communication. Molecular scattering provides a particularly direct route to generate entanglement. In this poster, we focus on both discrete-variable–discrete-variable (DV–DV) and continuous-variable–continuous-variable (CV–CV) entanglement generated in molecular collisions and chemical reactions. We present a formalism that directly relates entanglement measures to scattering matrix (S-matrix) elements and illustrate its applicability using three representative systems: Rb–Sr⁺ collisions, SrF–Rb collisions, and the chemical reaction F + HD.

For DV-DV entanglement, we demonstrate that scattering processes can generate large amounts of entanglement. Moreover, this entanglement can be efficiently controlled using an external magnetic field, exhibiting strong variability in the vicinity of a Feshbach resonance. In particular, for SrF–Rb collisions, we observe tunability of the entanglement from zero to unity, corresponding to complete control over its generation. In Rb–Sr⁺ collisions, we further show that DV–DV entanglement exhibits a pronounced dependence on the scattering angle.

For CV–CV entanglement, we show that the degree of entanglement is governed by the angular dependence of the differential cross section. We find that maximal CV–CV entanglement is achieved for inelastic transitions in the double s-wave regime, where both the initial and final scattering channels are dominated by s-wave contributions. Finally, we demonstrate that chemical reactions can also serve as an efficient mechanism for generating CV–V entanglement.