Continuous-variable quantum teleportation with non-Gaussian entangled states generated via multiple-photon subtraction and addition

TL;DR

This paper theoretically investigates how non-Gaussian entangled states, created by photon subtraction and addition, affect continuous-variable quantum teleportation, showing that symmetric photon subtraction enhances teleportation fidelity in low-squeezing regimes.

Contribution

It provides a detailed analysis of the effects of multiple-photon subtraction and addition on entanglement and teleportation performance, revealing conditions for enhancement and equivalence between operations.

Findings

Symmetric photon subtraction improves EPR correlation and teleportation fidelity at low squeezing.

Photon addition increases entanglement but reduces teleportation metrics compared to TMSVs.

One-mode photon subtraction and addition are equivalent and generally diminish key quantum properties.

Abstract

We theoretically analyze the Einstein-Podolsky-Rosen (EPR) correlation, the quadrature squeezing, and the continuous-variable quantum teleportation when considering non-Gaussian entangled states generated by applying multiple-photon subtraction and multiple-photon addition to a two-mode squeezed vacuum state (TMSVs). Our results indicate that in the case of the multiple-photon-subtracted TMSVs with symmetric operations, the corresponding EPR correlation, the two-mode squeezing degree, the sum squeezing, and the fidelity of teleporting a coherent state or a squeezed vacuum state can be enhanced for any squeezing parameter r and these enhancements increase with the number of subtracted photons in the low-squeezing regime, while asymmetric multiple-photon subtractions will generally reduce these quantities. For the multiple-photon-added TMSVs, although it holds stronger entanglement, its EPR correlation, two-mode squeezing, sum squeezing, and the fidelity of a coherent state are always smaller than that of the TMSVs. Only when considering the case of teleporting a squeezed vacuum state does the symmetric photon addition make somewhat of an improvement in the fidelity for large-squeezing parameters. In addition, we analytically prove that a one-mode multiple-photon-subtracted TMSVs is equivalent to that of the one-mode multiple-photon-added one. And one-mode multiple-photon operations will diminish the above four quantities for any squeezing parameter r.