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Limits on entanglement in rotationally-invariant scattering of spin systems

N. L. Harshman
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Abstract

This paper investigates the dynamical generation of entanglement in scattering systems, in particular two spin systems that interact via rotationally-invariant scattering. The spin degrees of freedom of the in-states are assumed to be in unentangled, pure states, as defined by the entropy of entanglement. Because of the restriction of rotationally-symmetric interactions, perfectly-entangling S-matrices, i.e. those that lead to a maximally entangled out-state, only exist for a certain class of separable in-states. Using Clebsch-Gordan coefficients for the rotation group, the scattering phases that determine the S-matrix are determined for the case of spin systems with $σ= 1/2$, 1, and 3/2.

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N. L. Harshman. 2006-02-02. Limits on entanglement in rotationally-invariant scattering of spin systems. https://doi.org/10.1103/physreva.73.062326

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