Exact decoherence-free state of two distant quantum systems in a non-Markovian environment

Understand

Decoherence-free state (DFS) encoding supplies a useful way to avoid the detrimental influence of the environment on quantum information processing.

• The DFS was previously well established in either the two subsystems locating at the same spatial position or the dynamics under the Born--Markovian approximation.
• Here, we investigate the exact DFS of two spatially separated quantum systems consisting of two-level systems or harmonic oscillators coupled to a common non-Markovian zero-temperature bosonic environment.
• The exact distance-dependent DFS and the explicit criterion for forming the DFS are obtained analytically, which reveals that the DFS can arise only in one-dimensional environment.