Source-linked AI summary
Nonlocal memory effects allow perfect teleportation with mixed states
Elsi-Mari Laine, Heinz-Peter Breuer, Jyrki Piilo
TL;DR
Noise can destroy perfect teleportation, and an optimized protocol cannot achieve perfection with the disturbed shared state. The protocol harnesses initial correlations between photon environments and has Bob apply local noise after standard teleportation. At perfect anticorrelation K = −1 (delta peak pump), perfect teleportation is achieved; for an uncorrelated distribution K = 0, no advantage with respect to the standard protocol can be gained.
Problem
Noise can destroy perfect teleportation, and an optimized protocol cannot achieve perfection with the disturbed shared state.
Source: p. 1Method
The protocol harnesses initial correlations between photon environments and has Bob apply local noise after standard teleportation.
Source: pp. 1, 3Results
At perfect anticorrelation K = −1 (delta peak pump), perfect teleportation is achieved; for an uncorrelated distribution K = 0, no advantage with respect to the standard protocol can be gained.
Source: p. 3Takeaways & Limitations
The protocol shows that non-Markovian memory effects can be a resource for overcoming noise in quantum communication.
Source: p. 4The analysis assumes a joint Gaussian frequency distribution and equal means and variances for photons 2 and 3.
Source: p. 3
Abstract
from arXiv · showhide
We show that perfect quantum teleportation can be achieved with mixed photon polarization states when nonlocal memory effects influence the dynamics of the quantum system. The protocol is carried out with a pair of photons, whose initial maximally entangled state is destroyed by local decoherence prior to teleportation. It is demonstrated that the presence of strong nonlocal memory effects, which arise from initial correlations between the environments of the photons, allow to restore perfect teleportation. We further analyze how the amount of initial correlations within the environment affects the fidelity of the protocol, and find that for a moderate amount of correlations the fidelity exceeds the one of the previously known optimal teleportation protocol without memory effects. Our results show that memory effects can be exploited in harnessing noisy quantum systems for quantum communication and that non-Markovianity is a resource for quantum information tasks.