Full decoherence induced by local fields in open spin chains with strong boundary couplings

TL;DR

This paper demonstrates that in an open XYZ spin chain with boundary reservoirs, tuning local magnetic fields near the boundaries can induce full decoherence, transforming the steady state into an uncorrelated infinite-temperature Gibbs state.

Contribution

It reveals how local field adjustments can control the steady state of boundary-driven spin chains, leading to complete decoherence under specific conditions.

Findings

Full decoherence achieved by tuning boundary fields

Dependence of decoherence conditions on chain parity and anisotropy

Critical manifold in field space where the transition occurs

Abstract

We investigate an open $XYZ$ spin $1/2$ chain driven out of equilibrium by boundary reservoirs targeting different spin orientations, aligned along the principal axes of anisotropy. We show that by tuning local magnetic fields, applied to spins at sites near the boundaries, one can change any nonequilibrium steady state to a fully uncorrelated Gibbsian state at infinite temperature. This phenomenon occurs for strong boundary coupling and on a critical manifold in the space of the fields amplitudes. The structure of this manifold depends on the anisotropy degree of the model and on the parity of the chain size.