Quantum correlation protection through spin self-rephasing in a one-dimensional Bose gas

A system consisting of a number of trapped two-level atoms in the presence of external inhomogeneous magnetic field undergoes dephasing: classically, since each atom feels a different field along its trajectory, the pseudospin rotation rates differ; as a result the average spin decays. It has been demonstrated in recent years that in the case of systems initiated in the atomic coherent state such spin dephasing can be prevented by tuning the interaction between the atoms to induce so-called spin self-rephasing. While the effect has been studied theoretically from a semiclassical point of view, a quantum-mechanical description is limited. In this paper we provide a numerical simulation of an ab initio model and provide realistic examples of spin self-rephasing used to counteract the effect of inhomogeneous magnetic field. We found that the spin self-rephasing method can be also used to prevent atomic squeezed states from decoherence: while the dephasing inhibition is lower as compared with the case of coherent states, it is still comparatively large and may be useful in real interferometric scenarios.