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.
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.
In this work, we investigate the performance of non-Gaussian entangled resources in continuous-variable quantum teleportation within a realistic setting. We describe the characteristic functions of three distinct entangled resources, a two-mode squeezed vacuum state, a two-mode photon-subtracted squeezed state, and a two-mode photon-added squeezed state. We extend the theoretical analysis by Yang et al. to include the realistic experimental conditions such as photon losses, imperfect measurements which typically affect continuous-variable quantum teleportation. Our results demonstrate that even in non-ideal situations, the photon-subtracted squeezed state outperforms the other two resources in the low squeezing regime, keeping fidelity above the classical threshold that suggests the robustness of photon-subtracted squeezed state in practical teleportation applications. We further analyze the EPR correlations of these entangled resources, revealing that the photon-subtracted squeezed state exhibits stronger EPR correlations than the original two-mode squeezed vacuum state and the two-mode photon-added squeezed state. This study merges theoretical models with realistic imperfections and utilizes non-Gaussian entanglement into high-fidelity quantum teleportation.
The need for high-fidelity quantum teleportation arises in a variety of quantum algorithms and protocols. Unfortunately, conventional continuous-variable teleportation schemes rely on Einstein–Podolsky–Rosen states that yield a fidelity that approaches unity only in the limit of an unphysical amount of squeezing. A new method that utilizes an ensemble of single photon entangled states, qubits, to teleport continuous variable (CV) states with fidelity approaching unity with finite resources was recently proposed by Andersen and Ralph [Phys. Rev. Lett.111, 050504 (2013)]. We extend these ideas to consider the general case of using maximally entangled d-level states, qudits, to teleport a CV state and discuss how the corresponding results are affected. In particular, we find that, by using qudits with dimension greater than two, we can achieve a higher fidelity with comparable resources.
Traditional continuous-variable teleportation can only approach unit fidelity in the limit of an infinite (and unphysical) amount of squeezing. We describe a new method for continuous-variable teleportation that approaches unit fidelity with finite resources. The protocol is not based on squeezed states as in traditional teleportation but on an ensemble of single photon entangled states. We characterize the teleportation scheme with coherent states, mesoscopic superposition states, and two-mode squeezed states and we find several situations in which near-unity teleportation fidelity can be obtained with modest resources.
Preserving entanglement during the teleportation of multipartite quantum states is a central challenge in continuous-variable quantum communication, particularly when experimentally feasible finite-dimensional entangled resources are employed. In this work, we investigate whether the entanglement of a two-mode continuous-variable state can be preserved when only one of its modes is teleported through a multimode interferometry-based protocol using a three-dimensional discrete entangled channel. Two representative entangled states, namely the two-mode squeezed vacuum and discrete-modulation states, are considered under both ideal conditions and four standard quantum noise channels: bit-flip, phase-flip, depolarizing, and amplitude-damping. The protocol is evaluated in terms of teleportation fidelity, success probability, logarithmic negativity, Wigner-function evolution, and state purity to provide a comprehensive assessment of both teleportation quality and entanglement preservation. The results show that, in the absence of noise, the protocol preserves most of the initial entanglement while maintaining high teleportation fidelity. Under noisy conditions, the residual entanglement remains remarkably robust against amplitude-damping and phase-flip noise, whereas bit-flip noise causes the most pronounced degradation. The phase-space structure and purity of the teleported states are likewise largely retained over a broad range of noise strengths. These findings demonstrate that multimode interferometry with finite-dimensional entangled channels provides an effective and noise-resilient approach for preserving continuous-variable entanglement during quantum teleportation, offering a practical route toward realistic quantum communication networks.
Preserving entanglement during the teleportation of multipartite quantum states is a central challenge in continuous-variable quantum communication, particularly when experimentally feasible finite-dimensional entangled resources are employed. In this work, we investigate whether the entanglement of a two-mode continuous-variable state can be preserved when only one of its modes is teleported through a multimode interferometry-based protocol using a three-dimensional discrete entangled channel. Two representative entangled states, namely the two-mode squeezed vacuum and discrete-modulation states, are considered under both ideal conditions and four standard quantum noise channels: bit-flip, phase-flip, depolarizing, and amplitude-damping. The protocol is evaluated in terms of teleportation fidelity, success probability, logarithmic negativity, Wigner-function evolution, and state purity to provide a comprehensive assessment of both teleportation quality and entanglement preservation. The results show that, in the absence of noise, the protocol preserves most of the initial entanglement while maintaining high teleportation fidelity. Under noisy conditions, the residual entanglement remains remarkably robust against amplitude-damping and phase-flip noise, whereas bit-flip noise causes the most pronounced degradation. The phase-space structure and purity of the teleported states are likewise largely retained over a broad range of noise strengths. These findings demonstrate that multimode interferometry with finite-dimensional entangled channels provides an effective and noise-resilient approach for preserving continuous-variable entanglement during quantum teleportation, offering a practical route toward realistic quantum communication networks.
We investigate continuous variable quantum teleportation using non-Gaussian states of the radiation field as entangled resources. We compare the performance of different classes of degaussified resources, including two-mode photon-added and two-mode photon-subtracted squeezed states. We then introduce a class of two-mode squeezed Bell-like states with one-parameter dependence for optimization. These states interpolate between and include as subcases different classes of degaussified resources. We show that optimized squeezed Bell-like resources yield a remarkable improvement in the fidelity of teleportation both for coherent and nonclassical input states. The investigation reveals that the optimal non-Gaussian resources for continuous variable teleportation are those that most closely realize the simultaneous maximization of the content of entanglement, the degree of affinity with the two-mode squeezed vacuum, and the, suitably measured, amount of non-Gaussianity.