Challenges
Datasets
Workspaces
Papers
Discussions
Leaderboard
Log inSign up
Challenges
Datasets
Workspaces
Papers
Discussions
Leaderboard
Blog
Job Board
Q3AS

© 2026 Aqora Quantum S.A.S.

TermsPrivacyLegal Notice

Proceedings of SPIE, the International Society for Optical Engineering/Proceedings of SPIE

Optimum teleportation with imperfect Bell-state measurements

Jaroslav Řeháček, Z. Hradil, Jaromı́r Fiurášek, Časlav Brukner

Published Jul 23, 2002• 0 citations
Publisher

Abstract

We study teleportation of qubits with imperfect Bell analysis on the sender's side. For the chosen family of Alice's measurements we find Bob's operations maximizing the overall fidelity of the teleportation protocol. In certain cases the optimum maps turn out to be nonunitary operations. This means that decoherence can sometimes enhance the performance of quantum teleportation protocols.

DOI
10.1117/12.475881

Related papers

Designing optimum completely positive maps for quantum teleportation

Jaroslav Řeháček, Z. Hradil, Jaromı́r Fiurášek +1 more

We study a general teleportation scheme with an arbitrary state of the pair of particles $(2$ and $3)$ shared by Alice and Bob, and arbitrary measurements on the input particle 1 and one of the members (2) of the pair on Alice's side. We find an efficient iterative algorithm for identifying optimum operations on Bob's side. In particular, we find that simple unitary transformations on his side are not always optimal even if particles 2 and 3 are perfectly entangled. We describe the most interesting protocols in the language of extremal completely positive maps.

arXiv:quant-ph/0105119•Physical Review A•Nov 8, 2001•15 citations

Quantum teleportation with partially entangled joint measurements induced by coherent errors

Jeonghyeon Shin, Jaehak Lee, Soojoon Lee +1 more

Quantum teleportation is a fundamental protocol in quantum information science, whose performance is conventionally evaluated under the assumption of ideal Bell-state measurements. In realistic implementations, however, joint measurements are often imperfect and can deviate from maximally entangled bases due to coherent errors in entangling operations. In this work, we analytically show how the entanglement of joint measurements determines teleportation performance, and we propose a strategy to overcome the limitations imposed by partially entangled joint measurements to recover the unit teleportation fidelity with a nonzero success probability. This is achieved by optimizing a reversing operation on the teleported state to compensate for the known coherent deformation of the Bell-state measurement. We then derive an exact equation revealing a quantitative relation between measurement entanglement, channel entanglement, and the success probability to realize the unit-fidelity two-qubit teleportation. We illustrate our results using elegant joint measurements and realistic coherent error models arising from imperfect entangling operations in quantum systems. Our work provides fundamental insight into the role of measurement entanglement in quantum teleportation and offers a practical framework for achieving faithful teleportation without requiring substantial modifications to existing hardware.

quant-pharXiv:2605.12130•Physical Review A•May 13, 2026•0 citations

Optimal partial deterministic quantum teleportation of qubits

Ladislav Mišta, Radim Filip

We propose a protocol implementing optimal partial deterministic quantum teleportation for qubits. This is a teleportation scheme realizing deterministically an optimal $1\ensuremath{\rightarrow}2$ asymmetric universal cloning where one imperfect copy of the input state emerges at the sender's station while the other copy emerges at receiver's possibly distant station. The optimality means that the fidelities of the copies saturate the asymmetric cloning inequality. The performance of the protocol relies on the partial deterministic nondemolition Bell measurement that allows us to continuously control the flow of information among the outgoing qubits. We also demonstrate that the measurement is optimal two-qubit operation in the sense of the trade-off between the state disturbance and the information gain.

Physical Review A•Feb 24, 2005•9 citations

Near perfect noisy quantum teleportation by one-sided environment engineering

Md Manirul Ali, Sovik Roy, Dipankar Home

Achieving near-unity fidelity of Quantum Teleportation (QT) in a noisy environment is an essential requirement for its real-world applications. Towards this goal, we devise a distinctive protocol based on the timing of the sender Alice's Bell-basis measurement, synchronous with the suitably engineered structure of noise in the receiver Bob's wing, without requiring any knowledge or manipulation of Alice's local noise. For this purpose, to finally obtain the teleported states by performing the required unitary operations, Bob has to retain his qubits for only two particular Bell-basis outcomes communicated by Alice, whose corresponding reduced states have no dependence on the noise parameters in Alice's wing. Such postselection is crucial for enhancing the fidelity of the teleported state towards its ideal limit, while ensuring its full independence of Alice's noise. We formulate the specifics of our protocol in terms of a generic two-level quantum system, subjected to a general non-Markovian spin-boson model for dephasing noise. The proposed scheme is illustrated by using any pure maximally/non-maximally entangled state as well as a Werner-type mixed state as resource. In particular, using resource states having small values of entanglement measure, we show that the high fidelity of QT is achievable in the presence of noise. Further, using our scheme, considering even the local regime of Werner states, wherein the Bell-CHSH inequalities are not violated, we show that the QT fidelity in the presence of noise can be appreciably high.

quant-pharXiv:2602.19103•Feb 24, 2026•0 citations

Quantum teleportation by using a genuinely entangled seven-qubit state

XinMei SUN, YaJun DUAN, Xin-Wei Zha

It is shown that a maximally seven-qubit state can be utilized for perfect teleportation of arbitrary three qubit systems and controlled teleportation of an arbitrary three qubit state. For perfect teleportation, the sender first performs a Von-Neumann measurement on her qubits, then the sender(Alice) tells the measurement result to the receiver(Bob) via a classical channel, the receiver can reconstruct the original state by performing appropriate unitary transformations on his qubits at hand. For controlled teleportation, the sender firstly carries out proper Bell-state measurements and the controller(charlie) needs to operate a single-qubit measurement, the receiver can reconstruct the original state by applying appropriate unitary transformations on his qubits after he knows the measurement results of both the sender and controller. Besides, the two teleportation schemes can be realized with the maximal probability.

Zhongguo kexue. Wulixue Lixue Tianwenxue•May 1, 2014•4 citations

Optimal fidelity of teleportation of coherent states and entanglement

Andrea Mari, David Vitali

We study the Braunstein-Kimble protocol for the continuous variable teleportation of a coherent state. We determine lower and upper bounds for the optimal fidelity of teleportation, maximized over all local Gaussian operations for a given entanglement of the two-mode Gaussian state shared by the sender (Alice) and the receiver (Bob). We also determine the optimal local transformations at Alice and Bob sites and the corresponding maximum fidelity when one restricts to local trace-preserving Gaussian completely positive maps.

arXiv:0808.2829•Physical Review A•Dec 31, 2008•41 citations
We study teleportation of qubits with imperfect Bell analysis on the sender's side. For the chosen family of Alice's measurements we find Bob's operations maximizing the overall fidelity of the teleportation protocol. In certain cases the optimum maps turn out to be nonunitary operations. This means that decoherence can sometimes enhance the performance of quantum teleportation protocols.
We study a general teleportation scheme with an arbitrary state of the pair of particles (2(2(2 and 3)3)3) shared by Alice and Bob, and arbitrary measurements on the input particle 1 and one of the members (2) of the pair on Alice's side. We find an efficient iterative algorithm for identifying optimum operations on Bob's side. In particular, we find that simple unitary transformations on his side are not always optimal even if particles 2 and 3 are perfectly entangled. We describe the most interesting protocols in the language of extremal completely positive maps.
Quantum teleportation is a fundamental protocol in quantum information science, whose performance is conventionally evaluated under the assumption of ideal Bell-state measurements. In realistic implementations, however, joint measurements are often imperfect and can deviate from maximally entangled bases due to coherent errors in entangling operations. In this work, we analytically show how the entanglement of joint measurements determines teleportation performance, and we propose a strategy to overcome the limitations imposed by partially entangled joint measurements to recover the unit teleportation fidelity with a nonzero success probability. This is achieved by optimizing a reversing operation on the teleported state to compensate for the known coherent deformation of the Bell-state measurement. We then derive an exact equation revealing a quantitative relation between measurement entanglement, channel entanglement, and the success probability to realize the unit-fidelity two-qubit teleportation. We illustrate our results using elegant joint measurements and realistic coherent error models arising from imperfect entangling operations in quantum systems. Our work provides fundamental insight into the role of measurement entanglement in quantum teleportation and offers a practical framework for achieving faithful teleportation without requiring substantial modifications to existing hardware.
We propose a protocol implementing optimal partial deterministic quantum teleportation for qubits. This is a teleportation scheme realizing deterministically an optimal $1\ensuremath{\rightarrow}2$ asymmetric universal cloning where one imperfect copy of the input state emerges at the sender's station while the other copy emerges at receiver's possibly distant station. The optimality means that the fidelities of the copies saturate the asymmetric cloning inequality. The performance of the protocol relies on the partial deterministic nondemolition Bell measurement that allows us to continuously control the flow of information among the outgoing qubits. We also demonstrate that the measurement is optimal two-qubit operation in the sense of the trade-off between the state disturbance and the information gain.
Achieving near-unity fidelity of Quantum Teleportation (QT) in a noisy environment is an essential requirement for its real-world applications. Towards this goal, we devise a distinctive protocol based on the timing of the sender Alice's Bell-basis measurement, synchronous with the suitably engineered structure of noise in the receiver Bob's wing, without requiring any knowledge or manipulation of Alice's local noise. For this purpose, to finally obtain the teleported states by performing the required unitary operations, Bob has to retain his qubits for only two particular Bell-basis outcomes communicated by Alice, whose corresponding reduced states have no dependence on the noise parameters in Alice's wing. Such postselection is crucial for enhancing the fidelity of the teleported state towards its ideal limit, while ensuring its full independence of Alice's noise. We formulate the specifics of our protocol in terms of a generic two-level quantum system, subjected to a general non-Markovian spin-boson model for dephasing noise. The proposed scheme is illustrated by using any pure maximally/non-maximally entangled state as well as a Werner-type mixed state as resource. In particular, using resource states having small values of entanglement measure, we show that the high fidelity of QT is achievable in the presence of noise. Further, using our scheme, considering even the local regime of Werner states, wherein the Bell-CHSH inequalities are not violated, we show that the QT fidelity in the presence of noise can be appreciably high.
It is shown that a maximally seven-qubit state can be utilized for perfect teleportation of arbitrary three qubit systems and controlled teleportation of an arbitrary three qubit state. For perfect teleportation, the sender first performs a Von-Neumann measurement on her qubits, then the sender(Alice) tells the measurement result to the receiver(Bob) via a classical channel, the receiver can reconstruct the original state by performing appropriate unitary transformations on his qubits at hand. For controlled teleportation, the sender firstly carries out proper Bell-state measurements and the controller(charlie) needs to operate a single-qubit measurement, the receiver can reconstruct the original state by applying appropriate unitary transformations on his qubits after he knows the measurement results of both the sender and controller. Besides, the two teleportation schemes can be realized with the maximal probability.
We study the Braunstein-Kimble protocol for the continuous variable teleportation of a coherent state. We determine lower and upper bounds for the optimal fidelity of teleportation, maximized over all local Gaussian operations for a given entanglement of the two-mode Gaussian state shared by the sender (Alice) and the receiver (Bob). We also determine the optimal local transformations at Alice and Bob sites and the corresponding maximum fidelity when one restricts to local trace-preserving Gaussian completely positive maps.