Correlations transference and apparition of a metastable decoherence-free subspace in dissipative reservoirs

TL;DR

This paper investigates how correlations transfer between a two-mode quantum field and its environment, revealing the emergence of metastable decoherence-free subspaces influenced by the amplitude of entangled states.

Contribution

It demonstrates the formation of metastable decoherence-free subspaces in both the system and reservoir, depending on the entangled states' amplitude, and analyzes correlation transfer dynamics.

Findings

Correlations are transferred from the quantum field to the environment during decoherence.

A metastable decoherence-free subspace appears, whose lifetime depends on photon number.

Quantum correlations are preserved within the DFS during its existence.

Abstract

The dynamic of correlations in a system composed of a two-mode quantum field coupled with the environment is studied. The quantum field corresponds to two entangled coherent states whose amplitude we vary up to the mesoscopic regime. We show that under the onset of decoherence, correlations in the quantum field are not lost but transferred to the environment. We also found that sudden transitions in the decoherence regimes appear along with the dynamics depending on the coherent states' amplitude. Increasing the amplitude of the entangled coherence state results in the apparition of a metastable decoherence-free subspace (DFS) in the field subsystem, and the transference of classical correlations freezes. This subspace only exists during a time interval that depends on the average number of photons. Interestingly, the reservoir subsystem also experiences the apparition of a DFS. Only quantum correlations are transferred while the DFS exists.