Quantum cryptography with perfect multiphoton entanglement.

J Opt Soc Am A Opt Image Sci Vis

Department of Electronic Engineering, The Chinese University of Hong Kong, Shatin, N T, Hong Kong, China.

Published: May 2005

Multiphoton entanglement in the same polarization has been shown theoretically to be obtainable by type-I spontaneous parametric downconversion (SPDC), which can generate bright pulses more easily than type-II SPDC. A new quantum cryptographic protocol utilizing polarization pairs with the detected type-I entangled multiphotons is proposed as quantum key distribution. We calculate the information capacity versus photon number corresponding to polarization after considering the transmission loss inside the optical fiber, the detector efficiency, and intercept-resend attacks at the level of channel error. The result compares favorably with all other schemes employing entanglement.

Download full-text PDF

Source
http://dx.doi.org/10.1364/josaa.22.001003DOI Listing

Publication Analysis

Top Keywords

multiphoton entanglement
8
quantum cryptography
4
cryptography perfect
4
perfect multiphoton
4
entanglement multiphoton
4
entanglement polarization
4
polarization theoretically
4
theoretically obtainable
4
obtainable type-i
4
type-i spontaneous
4

Similar Publications

Article Synopsis
  • Quantum conference key agreement (QCKA) allows secure sharing of conference keys among several participants, but current methods using entangled photons face limitations in key rate and scalability due to practical challenges.
  • The proposed source-independent QCKA utilizes the post-matching method, which can work within existing entangled photon distribution networks, ensuring unconditional security even against sophisticated attacks.
  • By improving the conference key rate from O(η) in previous protocols, the new approach shows significant advantages in performance over long distances, suggesting promising applications for future quantum networks.
View Article and Find Full Text PDF

Imaging Brain Tissue with Quantum Light at Low Power.

J Phys Chem B

November 2024

Department of Chemistry, University of Michigan, Ann Arbor, Michigan 48109, United States.

Light-induced tissue damage is a crucial limitation for traditional microscopy of the living brain, underscoring the need for new techniques that minimize exposure of samples to light. Here, we tested the hypothesis that quantum light, i.e.

View Article and Find Full Text PDF

Direct generation of time-energy-entangled W triphotons in atomic vapor.

Sci Adv

September 2024

National Laboratory of Solid State Microstructures, College of Engineering and Applied Sciences and School of Physics, Nanjing University, Nanjing 210093, China.

Article Synopsis
  • Entangled multiphoton sources are crucial for testing quantum theories and enhancing optical quantum technologies, and previous methods focused on using existing biphoton sources.
  • The authors introduce a novel technique for generating high-rate, time-energy-entangled W-class triphotons using spontaneous six-wave mixing in a specialized atomic vapor cell.
  • This new method provides long temporal coherence and adjustable waveforms, making it promising for applications in quantum communications and entanglement research.
View Article and Find Full Text PDF

Deterministic photon source of genuine three-qubit entanglement.

Nat Commun

September 2024

Center for Hybrid Quantum Networks (Hy-Q), The Niels Bohr Institute, University of Copenhagen, Copenhagen Ø, Denmark.

Deterministic photon sources allow long-term advancements in quantum optics. A single quantum emitter embedded in a photonic resonator or waveguide may be triggered to emit one photon at a time into a desired optical mode. By coherently controlling a single spin in the emitter, multi-photon entanglement can be realized.

View Article and Find Full Text PDF

With an extremely high dimensionality, the spatial degree of freedom of entangled photons is a key tool for quantum foundation and applied quantum techniques. To fully utilize the feature, the essential task is to experimentally characterize the multiphoton spatial wave function including the entangled amplitude and phase information at different evolutionary stages. However, there is no effective method to measure it.

View Article and Find Full Text PDF

Want AI Summaries of new PubMed Abstracts delivered to your In-box?

Enter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!