The role of the non-Gaussianity plays in the enhancement of the fidelity in continuous variable quantum teleportation

TL;DR

This paper explores how non-Gaussian modifications to quantum states affect the fidelity of continuous-variable quantum teleportation, revealing that symmetry in photon subtraction enhances fidelity, but higher non-Gaussianity does not always improve performance.

Contribution

It demonstrates that symmetrical photon subtraction arrangements optimize fidelity, and that increased non-Gaussianity does not necessarily correlate with better teleportation performance.

Findings

Symmetrical photon subtraction arrangements yield higher fidelity.

Asymmetrical arrangements are optimal when total photon subtraction is fixed.

Higher non-Gaussianity does not always improve teleportation fidelity.

Abstract

We investigated the role of non-Gaussianity (nG) plays in the enhancement of the fidelity in continuous-variable quantum teleportation of ideal Braunstein and Kimble (BK) protocol for coherent states, theoretically. The de-Gaussification procedure is realized through subtracting photons on the two-mode squeezed vacuum state (TMSVs). We find that the high fidelity always refers to a symmetrical arrangement of photon subtractions on the different modes of the TMSVs. The non-Gaussian resources demonstrate commendable superiorities compare with the Gaussian resources only for symmetrical arrangements of photon subtractions, however, the asymmetrical arrangements do not. When the total number of photon subtractions be a constant, we find that the optimal nG procedure prefers the most asymmetrical arrangement of subtractions. This characteristic is not consistent with the result that the highest fidelity refers to a symmetrical case. Under the same squeezing parameter, a higher nG might not always lead to a higher fidelity.