Qudits and High-Dimensional Quantum Computing

Frontiers in Physics, Journal Year: 2020, Volume and Issue: 8

Published: Nov. 10, 2020

Qudit is a multi-level computational unit alternative to the conventional 2-level qubit. Compared qubit, qudit provides larger state space store and process information, thus can provide reduction of circuit complexity, simplification experimental setup enhancement algorithm efficiency. This review an overview qudit-based quantum computing covering variety topics ranging from building, design, methods. We first discuss gate universality gates including pi/8 gate, SWAP multi-level-controlled gate. then present version several representative algorithms Deutsch-Jozsa algorithm, Fourier transform, phase estimation algorithm. Finally we various physical realizations for computation such as photonic platform, iron trap, nuclear magnetic resonance.

Language: Английский

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A universal qudit quantum processor with trapped ions

Nature Physics, Journal Year: 2022, Volume and Issue: 18(9), P. 1053 - 1057

Published: July 21, 2022

Language: Английский

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Machine Learning-Based Classification of Vector Vortex Beams

Physical Review Letters, Journal Year: 2020, Volume and Issue: 124(16)

Published: April 20, 2020

Structured light is attracting significant attention for its diverse applications in both classical and quantum optics. The so-called vector vortex beams display peculiar properties contexts due to the nontrivial correlations between optical polarization orbital angular momentum. Here we demonstrate a new, flexible experimental approach classification of beams. We first describe platform generating arbitrary complex inspired photonic walks. then exploit recent machine learning methods---namely, convolutional neural networks principal component analysis---to recognize classify specific patterns. Our study demonstrates advantages resulting from use learning-based protocols construction characterization high-dimensional resources protocols.

Language: Английский

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Efficient Generation of High-Dimensional Entanglement through Multipath Down-Conversion

Physical Review Letters, Journal Year: 2020, Volume and Issue: 125(9)

Published: Aug. 28, 2020

High-dimensional entanglement promises to greatly enhance the performance of quantum communication and enable advantages unreachable by qubit entanglement. One great challenges, however, is reliable production, distribution, local certification high-dimensional sources In this Letter, we present an optical setup capable producing states with exceptionally high level scalability, control, quality that, together novel techniques, achieve highest amount recorded so far. We showcase in 32-spatial dimensions record fidelity maximally entangled state (F=0.933±0.001) introduce measurement efficient schemes certify formation (E_{oF}=3.728±0.006). Combined existing multicore fiber technology, our results will lay a solid foundation for construction networks.

Language: Английский

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Efficient Time-Bin Encoding for Practical High-Dimensional Quantum Key Distribution

Physical Review Applied, Journal Year: 2020, Volume and Issue: 14(1)

Published: July 17, 2020

High-dimensional quantum key distribution (QKD) allows achievement of information-theoretic secure communications, providing high key-generation rates, which cannot, in principle, be obtained by QKD protocols with binary encoding. Nonetheless, the amount experimental resources needed increases as states to detected belong a larger Hilbert space, thus raising costs practical high-dimensional systems. Here, we present an alternative scheme for fiber-based four-dimensional QKD, time and phase encoding one-decoy state technique. Quantum transmission is tested over different channel lengths up 145 km standard single-mode fiber, evaluating enhancement secret rate comparison three-state two-dimensional BB84 protocol, same setup. Our measurement simplified compact receiver, where only two single-photon detectors are necessary, making it cost-effective solution QKD.

Language: Английский

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Rays, waves, SU(2) symmetry and geometry: toolkits for structured light

Journal of Optics, Journal Year: 2021, Volume and Issue: 23(12), P. 124004 - 124004

Published: Nov. 4, 2021

Abstract Structured light refers to the ability tailor optical patterns in all its degrees of freedom, from conventional 2D transverse exotic forms 3D, 4D, and even higher-dimensional modes light, which break fundamental paradigms open new exciting applications for both classical quantum scenarios. The description diverse freedom can be based on different interpretations, e.g. rays, waves, states, that are assumptions approximations. In particular, recent advances highlighted exploiting geometric transformation under general symmetry reveal ‘hidden’ allowing access higher dimensional control light. this tutorial, I outline basics geometry describe starting basic mathematics physics SU(2) group, then generation complex states leading a deeper understanding structured with connections between rays classical. explosion related reviewed, including multi-particle tweezing, novel topological photonics, high-capacity communications, many others, that, finally, what future might hold rapidly evolving field.

Language: Английский

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Genuine High-Dimensional Quantum Steering

Physical Review Letters, Journal Year: 2021, Volume and Issue: 126(20)

Published: May 20, 2021

High-dimensional quantum entanglement can give rise to stronger forms of nonlocal correlations compared qubit systems, offering significant advantages for information processing. Certifying these correlations, however, remains an important challenge, in particular experimental setting. Here we theoretically formalise and experimentally demonstrate a notion genuine high-dimensional steering. We show that entanglement, as quantified by the Schmidt number, lead form steering, provably impossible obtain via lower dimensions. Exploiting connection between steering incompatibility measurements, derive simple two-setting inequalities, violation which guarantees presence hence certifies bound on number one-sided device-independent report inequalities using macro-pixel photon-pair certifying In particular, entangled state dimension $d=31$, our data minimum $n=15$.

Language: Английский

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Unlocking the high dimensional’ potential: Comparative analysis of qubits and qutrits in variational quantum neural networks

Neurocomputing, Journal Year: 2025, Volume and Issue: 623, P. 129404 - 129404

Published: Jan. 13, 2025

Language: Английский

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Quantum Communications in Future Networks and Services

Quantum Reports, Journal Year: 2020, Volume and Issue: 2(1), P. 221 - 232

Published: March 11, 2020

Over the last few years, we have witnessed an impressive growth of data traffic and a progressive Digital Transformation Industry Society: deployment ultra-broadband low latency network infrastructures (e.g., 5G) are leading to global digitalization several domains. These techno-economic trends expected continue even accelerate in next decade, at end which, 6G smart networks services will be exploited. Innovation drive economy into decade. This paper draws some technology applications scenarios for this horizon, where Quantum Optical Communications likely disrupt Information Technology (ICT) Telecommunications. Among enabling technologies solutions moving direction, briefly addresses: quantum optical switching computing, THz-to-optical conversions advanced metamaterials radio-optical programmable environments Artificial Intelligence. The concludes with description future application scenario, called Twin, above exploited provide such as: ultra-massive scale communications connected spaces ambient intelligence, holographic telepresence, tactile Internet, new paradigms brain computer interactions, innovative forms communications.

Language: Английский

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Scalable and effective multi-level entangled photon states: a promising tool to boost quantum technologies

Nanophotonics, Journal Year: 2021, Volume and Issue: 10(18), P. 4447 - 4465

Published: Nov. 9, 2021

Abstract Multi-level (qudit) entangled photon states are a key resource for both fundamental physics and advanced applied science, as they can significantly boost the capabilities of novel technologies such quantum communications, cryptography, sensing, metrology, computing. The benefits using photons applications draw on their unique properties: propagate over long distances while preserving state coherence, possess multiple degrees freedom (such time frequency) that allow scalable access to higher dimensional encoding, all maintaining low platform footprint complexity. In context out-of-lab use, generation processing through integrated devices off-the-shelf components in high demand. Similarly, multi-level entanglement detection must be experimentally practical, i.e., ideally requiring feasible single-qudit projections noise tolerance. Here, we focus optical Bell cluster critical technologies, well universal witness operators characterization. Time- frequency-entangled main considered this context. We review promising approach scalable, cost-effective these by frequency combs fiber-based devices, respectively. finally report an practical identification characterization technique based is valid any complex provides good compromise between experimental feasibility robustness. results reported here pave way toward boosting implementation widely accessible photonic platforms.

Language: Английский

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