Entangled pure steady states in harmonic chains with a two-mode squeezed reservoir

Abstract

We study theoretically a finite harmonic chain where the two central oscillators are damped into a two-mode squeezed reservoir. By suitably choosing the Hamiltonian of the chain, the entire chain can be stabilized into a pure entangled steady state, even if it starts in a mixed state. We identify a condition on the system parameters such that the corresponding chain evolves into a pure steady state. We then proceed to parametrize a class of stabilizable pure states. Our approach is based on reservoir engineering and is particularly applicable to optomechanical systems and superconducting quantum circuits.