High-Fidelity Teleportation of Continuous-Variable Quantum States Via Non-Ideal Qutrit Entangled Resources

TL;DR

The paper addresses the intrinsic fidelity limit of continuous-variable quantum teleportation with Gaussian resources by introducing entangled qutrit resources within a multimode interferometric framework. It extends prior qubit-based schemes to three-dimensional quantum channels, showing that high-fidelity teleportation can be achieved with fewer teleporter arms while maintaining a reasonable success probability. In the ideal case, 3D channels outperform 2D channels, with demonstrated improvements across multiple input states. Under realistic noise models, the authors quantify degradation via Kraus operators and logarithmic negativity, revealing that phase-flip noise is least detrimental and that the 3D approach remains robust with moderate noise, highlighting practical viability with current photonic technologies.

Abstract

Achieving near-unity fidelity in conventional continuous-variable quantum teleportation schemes based on two-mode squeezed vacuum states is fundamentally unattainable. To overcome this limitation, alternative approaches utilizing ensembles of two-dimensional entangled qubits have been proposed. In this work, we investigate continuous-variable quantum teleportation employing entangled qutrit resources under realistic noise effects. The results demonstrate that the proposed scheme performs well in both ideal and noisy conditions, enabling high-fidelity teleportation with a reasonable success probability.

Figures (7)

• Figure 1: Schematic of the teleportation scheme, including $N$ qutrit teleporters in a multimode interferometer, the input state is split into $N$ states, each of which is teleported by a qutrit teleporter. The teleported outputs are recombined in an N-splitter, and teleportation is successful if all photons exit through a single port.
• Figure 2: Teleportation with 2D and 3D channels for the input coherent state in terms of $\alpha$: (a) fidelity, (b) success probability, for different values ​​of $N$.
• Figure 3: Fidelity and success probability for different input states in the interferometric teleportation scheme; (left) Schrödinger cat input state as a function of the amplitude $\alpha$, (middle) Vacuum squeezed input state as a function of the squeezing parameter $\xi$, (right) TMSV input state as a function of the squeezing parameter $\lambda$.
• Figure 4: Logarithmic negativity of the teleportation channel as a function of the noise probability $P_{\text{noise}}$ for the bit-flip, phase-flip, and depolarizing noise models.
• Figure 5: Fidelity and success probability for the input coherent state under different quantum noises applied to the teleporters for $N=3$ and different values ​​of the noise probability $P_{\text{noise}}$; (left) bit-flip noise, (middle) phase-flip noise, (right) depolarizing noise.