Chaos in a two-spin system with applied magnetic field

Abstract

We observe both classical and quantum chaos in a system of two interacting magnetic moments in an applied magnetic field. Chaos in the classical system, as seen in the Poincar\'e surface of section, and chaos in the quantum system, as indicated by the changing patterns of the quantum web, appear at the same value of the applied magnetic field parameter. The signatures of chaos disappear in both the classical and quantum systems at a larger value of the field parameter.