Robustness of Non-Gaussian Entanglement against Noisy Amplifier and Attenuator Environments

The recently developed Kraus representation for bosonic Gaussian channels is employed to study analytically the robustness of non-Gaussian entanglement against evolution under noisy attenuator and amplifier environments, and compare it with the robustness of Gaussian entanglement. Our results show that some non-Gaussian states with one ebit of entanglement are more robust than all Gaussian states, even the ones with arbitrarily large entanglement, a conclusion of direct consequence to the recent conjecture by Allegra et al. [Phys. Rev. Lett. 105, 100503 (2010)].

Figure 1

Comparison of the robustness of the entanglement of a NOON state with that of two-mode Gaussian states under the two-sided action of symmetric noisy attenuator.

Figure 2

Comparison of the robustness of the entanglement of a PNES state with that of two-mode Gaussian states under the action of two-sided symmetric noisy attenuator.

Figure 3

Comparison of the robustness of the entanglement of a NOON state with that of all two-mode Gaussian states under the action of two-sided symmetric noisy amplifier.

Figure 4

Comparison of the robustness of the entanglement of a PNES state with that of all two-mode Gaussian states under the action of two-sided symmetric noisy amplifier.