Optimal subsystem approach to multi-qubit quantum state discrimination and experimental investigation

Xue, Shichuan; Wu, Junjie; Xu, Ping; Yang, Xuejun

doi:10.1007/s11433-017-9098-5

Cited by 5 publications

(5 citation statements)

References 35 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Quantum key distribution (QKD), proposed by Bennett and Brassard in 1984 (BB84) [10], is the earliest form of quantum communication. They pointed out that the core idea in the design of QKD protocols is to use non-orthogonal quantum states to support key agreement, since quantum principles such as the collapse of measurement and the nocloning theorem [11]- [14] guarantee its security. Since then, QKD has become one of the hottest frontiers and a large number of theoretical QKD solutions have been proposed.…”

Section: Introductionmentioning

confidence: 99%

Single-Photon-Memory Two-Step Quantum Secure Direct Communication Relying on Einstein-Podolsky-Rosen Pairs

Pan

Ruan

et al. 2020

IEEE Access

View full text Add to dashboard Cite

Quantum secure direct communication (QSDC) is an important branch of quantum communication that is capable of directly transmitting secret messages over a quantum channel. It may be viewed as a concrete realization of Wyner's wiretap channel theory, which ensures the reliable and secure communication of information in the presence of noise and eavesdropping. Hence it is a fully-fledged quantum-communications protocol, which does not require a separate secret key negotiation phase. By contrast, its quantum key distribution (QKD) counterpart represents a secret key-negotiation protocol, which has to be followed up by a separate classical communication session. The essential difference between these two modes of quantum communication lies in the employment of a block-based data transmission technique, proposed by Long and Liu in 2000. However, the original block-based data transmission requires quantum memory, which is not widely available at the time of writing. Recently, this difficulty has been overcome by using classical coding theory, which has been successfully applied to the single-qubit DL04 QSDC. Here we will present a single-photon-memory QSDC protocol based on entangled pairs of photons. We commence by comparing QSDC to QKD, followed by an example of the single-photon QSDC and single-photon QKD protocol. Then we continue by modifying the so-called two-step QSDC protocol designed for deterministic QKD by reducing the number of qubits in a block into a single one, in which Alice prepares Einstein-Podolsky-Rosen (EPR) photon pairs and partitions them into two parts: the so-called pioneer qubit and the follow-up qubit. The pioneer photon is transferred first to Bob, while the follow-up photon is used either for performing encoding or for eavesdropping detection. Bob extracts the candidate key by combining the two particles of the EPR pair to perform Bell-basis measurement. Then the protocol is transformed into a singlephoton-memory QSDC using coding theory. Our theoretical analysis shows that the resultant protocol is robust to individual attacks. Additionally, a high communication efficiency is achieved. INDEX TERMS Quantum secure direct communication, quantum key distribution, entanglement.

show abstract

Section: Introductionmentioning

confidence: 99%

Single-Photon-Memory Two-Step Quantum Secure Direct Communication Relying on Einstein-Podolsky-Rosen Pairs

Pan

Ruan

et al. 2020

IEEE Access

View full text Add to dashboard Cite

show abstract

“…-The discrimination between quantum states is a significant problem in quantum information theory [1] since a quantum state without any classical information cannot be cloned perfectly [2,3]. Usually, two strategies are employed in the quantum state discrimination [4][5][6][7][8][9][10][11][12][13][14][15][16][17][18][19][20]: minimum error discrimination [6][7][8][9][10][11][12], which identifies the state with minimum error probability and unambiguous discrimination [13][14][15][16][17][18][19][20], where the identification of the states is error-free with a minimum probability of inconclusive result.…”

mentioning

confidence: 99%

The universal unambiguous discriminator between two unknown qudit states

Wang

Zhou

2021

EPL

View full text Add to dashboard Cite

In this work, the unambiguous discrimination between two unknown states in d-dimensional Hilbert space is investigated. To achieve this goal, the Hilbert space of the states is divided into a series of subspaces, where the components of the two states projected in some of these subspaces can be unambiguously distinguished, and then the unambiguous discriminator between two unknown qudit states can be constructed. Moreover, the optimal success probability of the discrimination between two unknown states is obtained and the form of detection operators is given.

show abstract

“…Deterministic source of single photons is a vital resource for photonic quantum technologies such as boson sampling, [1] state discrimination, [2] and foundations of quantum mechanics. [3] From the requirement of practical experiments, single-photon sources should emit photons on-demand and indistinguishable in all degrees of freedom.…”

mentioning

confidence: 99%

“…[10] As an alternative approach, parametric sources have specific advantages in spectral tunability and integration. [11][12][13] Photon pairs can be produced on the integrated photonic chip [14,15] via nonlinear process such as the spontaneous fourwave mixing (SFWM) process in the χ (3) silicon [16] and in the χ (2) lithium niobate. [17,18] For heralded single-photon sources, one photon in a pair is detected to herald the existence of its partner.…”

mentioning

confidence: 99%

See 1 more Smart Citation

Near 100% spectral-purity photons from reconfigurable micro-rings*

Zhu

Liu

et al. 2020

Chinese Phys. B

Self Cite

View full text Add to dashboard Cite

We propose an on-chip reconfigurable micro-ring to engineer the spectral-purity of photons. The micro-ring resonator is designed to be coupled by one or two asymmetric Mach–Zehnder interferometers and the coupling coefficients hence the quality-factors of the pump and the converted photons can be dynamically changed by the interferometer’s internal phase-shifter. We calculate the joint-spectrum function and obtain the spectral-purity of photons and Schmidt number under different phases. We show that it is a dynamical method to adjust the spectral-purity and can optimize the spectral-purity of photons up to near 100%. The condition for high-spectral-purity photons is ensured by the micro-ring itself, so it overcomes the trade-off between spectral purity and brightness in the traditional post-filtering method. This scheme is robust to fabrication variations and can be successfully applied in different fabrication labs and different materials. Such high-spectral-purity photons will be beneficial for quantum information processing like Boson sampling and other quantum algorithms.

show abstract

Optimal subsystem approach to multi-qubit quantum state discrimination and experimental investigation

Cited by 5 publications

References 35 publications

Single-Photon-Memory Two-Step Quantum Secure Direct Communication Relying on Einstein-Podolsky-Rosen Pairs

Single-Photon-Memory Two-Step Quantum Secure Direct Communication Relying on Einstein-Podolsky-Rosen Pairs

The universal unambiguous discriminator between two unknown qudit states

Near 100% spectral-purity photons from reconfigurable micro-rings*

Contact Info

Product

Resources

About