Title: Universality of entanglement creation in low-energy two-dimensional scattering

We prove that the entanglement created in the low-energy scattering of two particles in two dimensions is given by a universal coefficient that is independent of the interaction potential. This is strikingly different from the three dimensional case, where it is proportional to the total scattering cross section. Before the collision the state is a product of two normalized Gaussians. We take the purity as the measure of the entanglement after the scattering. We give a rigorous computation, with error bound, of the leading order of the purity at low-energy. For a large class of potentials, that are not-necessarily spherically symmetric, we prove that the low-energy behavior of the purity, P, is universal. It is given by P=1−1/((ln(σ/ħ)){sup 2}) E, where σ is the variance of the Gaussians and the entanglement coefficient, E, depends only on the masses of the particles and not on the interaction potential. There is a strong dependence of the entanglement in the difference of the masses. The minimum is when the masses are equal, and it increases strongly with the difference of the masses. -- Highlights: •The entanglement in low-energy scattering in two dimensions is universal. It is independent of the potential. •We take themore » purity as the measure of entanglement. •We give a rigorous computation of the leading order of the purity at low energy. •The created entanglement depends strongly on the masses of the particles. •It takes its minimum for equal masses and it increases strongly with the difference of the masses.« less

Journal Name: Annals of Physics (New York); Journal Volume: 337; Other Information: Copyright (c) 2013 Elsevier Science B.V., Amsterdam, The Netherlands, All rights reserved.; Country of input: International Atomic Energy Agency (IAEA)