Reversible feedback confinement

Abstract

We present a feedback protocol that is able to confine a system to a single microstate without heat dissipation. The protocol adjusts the Hamiltonian of the system in such a way that the Bayesian posterior distribution after measurement is in equilibrium. As a result, the whole process satisfies feedback reversibility - the process is indistinguishable from its time reversal- and assures the lowest possible dissipation for confinement. In spite of the whole process being reversible it can surprisingly be implemented in finite time. We illustrate the idea with a Brownian particle in a harmonic trap with increasing stiffness and present a general theory of reversible feedback confinement for systems with discrete states. editor's choice Copyright (C) EPLA, 2016.