Overcoming Linear Dissipation by Designed Nonlinear Loss

Abstract

Artificially designed nonlinear loss is a rather novel and highly promising way to generate deterministically non-classical states of a bosonic mode. It has a number of advantages over more usual nonlinear unitary dynamics. Nonlinear coherent loss is able to produce a wide range of non-classical states, for example, arbitrary Fock states, and their finite and countable superpositions. Linear loss is inevitable in real systems. It can significantly degrade the quality of generated states. We propose the solution of this problem, based on combining nonlinear loss with coherent or incoherent (thermal) excitation of the mode. One can always build such a loss-resistant dissipative gadget that for some class of initial states the desired pure state can be attained for a certain time interval with an arbitrary precision. We also demonstrate that an arbitrarily strong linear loss can be still compensated by a sufficiently intensive coherent or even thermal driving thus attaining a strongly non-classical (in particular, sub-Poissonian) stationary mixed states.