Generating non-classical states from spin coherent states via interaction with ancillary spins

Abstract

The generation of non-classical states of large quantum systems has attracted much interest from a foundational perspective, but also because of the significant potential of such states in emerging quantum technologies. In this paper we consider the possibility of generating non-classical states of a system of spins by interaction with an ancillary system, starting from an easily prepared initial state . We extend previous results for an ancillary system comprising a single spin to bigger ancillary systems and the interaction strength is enhanced by a factor of the number of ancillary spins. Depending on initial conditions, we find -by a combination of approximation and numerics -that the system of spins can evolve to spin cat states, spin squeezed states or to multiple cat states. * We also discuss some candidate systems for implementation of the Hamiltonian necessary to generate these non-classical states.