Asymptotic entanglement capacity of the Ising and anisotropic Heisenberg interactions

Abstract

We calculate the asymptotic entanglement capacity of the Ising interaction \sigma_z\otimes\sigma_z, the anisotropic Heisenberg interaction \sigma_x\otimes\sigma_x + \sigma_y\otimes\sigma_y, and more generally, any two-qubit Hamiltonian with canonical form K = \mu_x \sigma_x\otimes \sigma_x + \mu_y \sigma_y \otimes \sigma_y. We also describe an entanglement assisted classical communication protocol using the Hamiltonian K with rate equal to the asymptotic entanglement capacity.