arXiv subjects

Chunqing Wu

Publications and source records attributed to Chunqing Wu.

4 recordsLinked to original sources

arXiv2025

Clock Synchronization for Drone-Based Entanglement Quantum Key Distribution

Drone-based entanglement distribution provides full spatiotemporal coverage for quantum networks, enabling quantum key distribution (QKD) in dynamic environments. The security of QKD fundamentally depends on high-fidelity quantum state measurements, for which high-precision clock synchronization is indispensable, as timing jitter is inversely correlated with quantum state fidelity. However, drone-based clock synchronization is constrained by SWaP (Size, Weight, and Power) limitations and dynamic mobility effects. Here, we propose a synchronization protocol for drone-based entanglement distribution, leveraging nanosecond-accurate Global Navigation Satellite System (GNSS) timing and entanglement-based timing correction to overcome SWaP constraints. Experimental results demonstrate 24 ps RMS synchronization in simulated free-space quantum channels with distance dynamics, without requiring precision reference clock. Our protocol enables drone-based entanglement distribution, paving the way for seamless wide-area and local-area quantum internet.

quant-ph↗

arXiv2021

General Quantum Bernoulli Factory: Framework Analysis and Experiments

The unremitting pursuit for quantum advantages gives rise to the discovery of a quantum-enhanced randomness processing named quantum Bernoulli factory (QBF). This quantum enhanced process can show its priority over the corresponding classical process through readily available experimental resources, thus in the near term it may be capable of accelerating the applications of classical Bernoulli factories, such as the widely used sampling algorithms. In this work, we provide the framework analysis of the QBF. We thoroughly analyze the quantum state evolution in this process, discovering the field structure of the constructible quantum states. Our framework analysis shows that naturally, the previous works can be described as specific instances of this framework. Then, as a proof of principle, we experimentally demonstrate this framework via an entangled two-photon source along with a reconfigurable photonic logic, and show the advantages of the QBF over the classical model through a classically infeasible instance. These results may stimulate the discovery of advantages of the quantum randomness processing in a wider range of tasks, as well as its potential applications.

quant-ph↗

arXiv2020

Sample caching Markov chain Monte Carlo approach to boson sampling simulation

Boson sampling is a promising candidate for quantum supremacy. It requires to sample from a complicated distribution, and is trusted to be intractable on classical computers. Among the various classical sampling methods, the Markov chain Monte Carlo method is an important approach to the simulation and validation of boson sampling. This method however suffers from the severe sample loss issue caused by the autocorrelation of the sample sequence. Addressing this, we propose the sample caching Markov chain Monte Carlo method that eliminates the correlations among the samples, and prevents the sample loss at the meantime, allowing more efficient simulation of boson sampling. Moreover, our method can be used as a general sampling framework that can benefit a wide range of sampling tasks, and is particularly suitable for applications where a large number of samples are taken.

quant-ph↗

arXiv2014

Link Reassignment based Snapshot Partition for Polar-orbit LEO Satellite Networks

Snapshot is a fundamental notion proposed for routing in mobile low earth orbit (LEO) satellite networks which is characterized with predictable topology dynamics. Its distribution has a great impact on the routing performance and on-board storage. Originally, the snapshot distribution is invariable by using the static snapshot partition method based on the mechanical steering antenna. Utilizing nowadays advanced phased-array antenna technology, we proposed a quasi-dynamic snapshot partition method based on the inter-satellite links (ISLs) reassignment for the polar-orbit LEO satellite networks. By steering the inter-satellite antennas when snapshot switches, we can reassign the ISLs and add available ISLs for a better following snapshot. Results show that our method can gain more stable routing performance by obtaining constant snapshot duration, constant ISL number and lower end to end delay. Especially for Iridium system, our method can gain not only longer merged snapshot duration, half of the snapshot number, but also higher utilization ratio of inter-plane ISLs. Potentially, our method could be very useful for the Iridium-next system.

cs.NI↗