Nonlinear dissipation can combat linear loss

Abstract

We demonstrate that it is possible to compensate for effects of strong linear loss when generating non-classical states by engineered nonlinear dissipation. We show that it is always possible to construct such a loss-resistant dissipative gadget in which, for a certain class of initial states, the desired non-classical pure state can be attained within a particular time interval with an arbitrary precision. Further we demonstrate that an arbitrarily large linear loss can still be compensated by a sufficiently strong coherent or even thermal driving, thus attaining a strongly non-classical (in particular, sub-Poissonian) stationary mixed states.Comment: Submitted to PR

Quantum tight-binding chains with dissipative coupling

“…Taking the continuous approximation and using the quantity γ ≪ m t 1 as small parameter, from equation (25) we straightforwardly obtain the following approximation: . Examples of exact solutions for initial states (25) are shown in figure 3. The panels ((a)-(d)) corresponds to = m 0, 1, 2, 3.…”

“…Notice, that the states (25) are non-correctly described within the bounds of the quasiclassical Fourier theory. The 'classical' averaging of states (25) as it is done in equations (22) and (23) can lead to the drastic deformation of them (for example, the states orthogonal to the stationary state will be reduced to zero by such averaging). Mind that polynomial decay regimes considered here are taking place for times, when initially localized excitation has spread far enough.…”

“…Moreover, combining coupling to the same reservoir with the nonlinear interaction between quantum systems, it is possible to produce nonlinear loss generating robustly a wide variety of non-classical states [22][23][24]. By adding external driving, a generated non-classical state can be preserved in the presence of an arbitrarily large linear loss [25].…”

“…Starting with the initial state(25) and choosing the coefficients f i in the form of the normalized binomial coefficients, the first non-zero term in the approximation (26) of the order of…”

Coherent Diffusive Photon Gun for Generating Nonclassical States

“…The practically reachable values of the Mandel parameter are approximately limited to Q = −0.8 (see also Ref. [29]). This minimal value is shifted to smaller interaction length by increasing the average number of photons in the initial state.…”