Related papers: Broadband optical time-domain reflectometry for se…
In real-life implementations of quantum key distribution (QKD), the physical systems with unwanted imperfections would be exploited by an eavesdropper. Based on imperfections in the detectors, detector control attacks have been successfully…
A long range phase-sensitive optical time domain reflectometer (phi-OTDR) with a multi-frequency non-linear frequency modulation (NLFM) optical pulse is proposed in this Letter. To boost the pulse energy while suppressing the optical…
Quantum key distribution (QKD) allows two distant parties to share encryption keys with security based on physical laws. Experimentally, it has been implemented with optical means, achieving key rates of 1.26 Megabit/s over 50 kilometres…
The influence of the laser frequency drift on the operation of phase-sensitive optical time-domain reflectometry ($\Phi$-OTDR) systems is considered. Theoretical results based on a new numerical $\Phi$-OTDR model demonstrating the influence…
Quantum key distribution (QKD) provides a theoretically secure method for cryptographic key exchange by leveraging quantum mechanics, but practical implementations face vulnerabilities such as Trojan horse attack on phase modulators. This…
We propose a newly configured optical correlation-domain reflectometry (OCDR) without the use of an electrical spectrum analyzer (ESA) for high-speed distributed reflectivity measurement with an enhanced spatial resolution. First, the…
A well-protected and characterised source in a quantum key distribution system is needed for its security. Unfortunately, the source is vulnerable to light-injection attacks, such as Trojan-horse, laser-seeding, and laser-damage attacks, in…
Quantum Key Distribution (QKD) can guarantee security for practical indoor optical wireless environments. The key challenges are to mitigate artificial lighting and ambient light at the receiver. A new spectral region for QKD is proposed…
High-speed quantum key distribution (QKD) systems have achieved repetition frequencies above gigahertz through advanced technologies and devices, laying an important foundation for the deployment of high-key-rate QKD system. Although these…
We demonstrate an experimental phase optical time-domain reflectometry (OTDR) system capable of simultaneous detection and classification of various environmental events, such as wind-induced fiber movement, vehicle movement, and audio…
The security of quantum communication using a weak coherent source requires an accurate knowledge of the source's mean photon number. Finite calibration precision or an active manipulation by an attacker may cause the actual emitted photon…
In this paper we investigate spectral vulnerabilities in quantum key distribution systems arising from the use of shorter-wavelength radiation in the 400-800 nm range, with particular focus on the induced photorefraction attack (IPA).…
Use of low-noise detectors can both increase the secret bit rate of long-distance quantum key distribution (QKD) and dramatically extend the length of a fibre optic link over which secure key can be distributed. Previous work has…
Optical diffraction tomography (ODT) is a powerful non-invasive 3D imaging technique, but its combination with broadband light sources is difficult. In this study, we introduce ultrabroadband ODT, covering over 150 nm of visible spectral…
Twin-field quantum key distribution (TF-QKD) promises ultra-long secure key distribution which surpasses the rate distance limit and can reduce the number of the trusted nodes in long-haul quantum network. Tremendous efforts have been made…
The FTTH (Fiber To The Home) market currently needs new network maintenance technologies that can, economically and effectively, cope with massive fiber plants. However, operating these networks requires adequate means for an effective…
In this paper, we report on the development progress of correlation-based optical time domain reflectometry (OTDR). Substituting the direct detection receiver with a coherent receiver enables to extract the phase and polarization…
Coherent one-way quantum key distribution (COW-QKD) has been widely investigated, and even been deployed in real-world quantum network. However, the proposal of the zero-error attack has critically undermined its security guarantees, and…
We present a novel distributed Brillouin optical time domain reflectometer (BOTDR) using standard telecommunication fibers based on single-photon avalanche diodes (SPADs) in gated mode, hd-BOTDR, with a range of 120 km and 10 m spatial…
Quantum key distribution (QKD) enables secure communication by harnessing the fundamental principles of quantum physics, which inherently guarantee information-theoretic security and intrinsic resistance to quantum computing attacks.…