Effect of weak measurement on entanglement distribution over noisy channels

Abstract

Being able to implement effective entanglement distribution in noisy environments is a key step towards practical quantum communication, and long-term efforts have been made on the development of it. Recently, it has been found that the null-result weak measurement (NRWM) can be used to enhance probabilistically the entanglement of a single copy of amplitude-damped entangled state. This paper investigates remote distributions of bipartite and multipartite entangled states in the amplitudedamping environment by combining NRWMs and entanglement distillation protocols (EDPs). We show that the NRWM has no positive effect on the distribution of bipartite maximally entangled states and multipartite Greenberger-Horne-Zeilinger states, although it is able to increase the amount of entanglement of each source state (noisy entangled state) of EDPs with a certain probability. However, we find that the NRWM would contribute to remote distributions of multipartite W states. We demonstrate that the NRWM can not only reduce the fidelity thresholds for distillability of decohered W states, but also raise the distillation efficiencies of W states. Our results suggest a new idea for quantifying the ability of a local filtering operation in protecting entanglement from decoherence.

Tripartite Entanglement: Foundations and Applications

“…In [217], GHZ states are considered for remote state preparation of quantum states in noisy environments. The relationship between weak measurement and GHZ entanglement distribution in the presence of noise also it was investigated [218]. The robustness of GHZ and W states against decoherence it was experimentally investigated in [219].…”

Dissipative dynamics of an entangled three-qubit system via non-Hermitian Hamiltonian: Its correspondence with Markovian and non-Markovian regimes

“…For instance, quantum teleportation protocols, based on three-qubit (or in general multi-qubit) entangled states, are widely used in order to construct quantum networks in the theoretical [31][32][33][34] and practical [35][36][37] researches, especially for their applications in the content of weak measurement and quantum measurement reversal. [38][39][40] As an example, the extension of entanglement in superconducting circuits, which has been so far limited to two qubits, to three, eight and ten qubits has been achieved among spins, ions and photons, respectively. [41] Motivating by the above-mentioned facts, in the present work we study the entanglement dynamics of an entangled "three-qubit" system in the presence of dissipation via extend-ing the presented approach in Refs.…”

Improving the Robustness of Entangled States by Basis Transformation

“…Quantum filtration methods could be used to probabilistically increase the fidelity of source states with particular structures such that it meets the threshold required for an entanglement distillation protocol [ 40 , 41 ]. However, quantum filtering operations may decrease the final distillation efficiency in the case where the entanglement degree of the source states exceeds the required threshold [ 42 ]. Enhancing the intrinsic robustness of entangled states is thus of importance [ 43 , 44 , 45 , 46 , 47 ].…”