A5100717689- Quantum Information and Cryptography
- Quantum optics and atomic interactions
- Atomic and Subatomic Physics Research
- Quantum Computing Algorithms and Architecture
- Quantum Mechanics and Applications
- Cold Atom Physics and Bose-Einstein Condensates
- Advanced Fiber Laser Technologies
- Advanced Frequency and Time Standards
- Orbital Angular Momentum in Optics
- Random lasers and scattering media
- Mechanical and Optical Resonators
- Laser-Matter Interactions and Applications
- Optical Wireless Communication Technologies
- Optical Network Technologies
- Advanced MRI Techniques and Applications
- Chaos-based Image/Signal Encryption
- Open Education and E-Learning
- Semiconductor Lasers and Optical Devices
- Photonic and Optical Devices
- Advanced Photonic Communication Systems
- Laser-Plasma Interactions and Diagnostics
- Spectroscopy and Laser Applications
- Quantum, superfluid, helium dynamics
- Quantum-Dot Cellular Automata
- Advanced Optical Imaging Technologies
Peking University
2016-2025
Institute of Forest Resource Information Techniques
2009-2024
Chinese Academy of Forestry
2009-2024
State Key Laboratory of Nonferrous Metals and Processes
2020-2024
Institute of Forensic Science
2022-2024
General Research Institute for Nonferrous Metals (China)
2011-2024
Hankou University
2024
State Forestry and Grassland Administration
2024
Grinm Advanced Materials (China)
2020-2024
University of Chinese Academy of Sciences
2024
Quantum key distribution provides secure keys resistant to code-breaking quantum computers. The continuous-variable version of offers the advantages higher secret rates in metropolitan areas, as well use standard telecom components that can operate at room temperature. However, transmission distance these systems (compared with discrete-variable systems) are currently limited and considered unsuitable for long-distance distribution. Herein, we report experimental results long over 202.81 km...
Privacy amplification is an indispensable step in postprocessing of continuous-variable quantum key distribution (CV-QKD), which used to distill unconditional secure keys from identical corrected between two distant legal parties. The processing speed privacy has a significant effect on the secret rate CV-QKD system. We report high-speed parallel implementation length-compatible algorithm based graphic unit. Length-compatible satisfy security requirement at different transmission distances...
We propose a continuous-variable measurement-device-independent quantum key distribution (CV-MDI QKD) protocol, in which detection is conducted by an untrusted third party. Our protocol can defend all detector side channels, seriously threaten the security of practical CV QKD system. Its analysis against arbitrary collective attacks derived based on fact that entanglement-based scheme CV-MDI equivalent to conventional with coherent states and heterodyne detection. find maximal total...
The continuous-variable version of quantum key distribution (QKD) offers the advantages (over discrete-variable systems) higher secret rates in metropolitan areas as well use standard telecom components that can operate at room temperature. An important step real-world adoption QKD is deployment field tests over commercial fibers. Here we report two different a system through fiber networks Xi'an and Guangzhou distances 30.02 km (12.48 dB) 49.85 (11.62 dB), respectively. We achieve secure...
High-sensitivity total-field atomic magnetometer enables brain-activity measurements in unshielded Earth’s field.
Abstract Continuous-variable quantum key distribution (CVQKD) offers the specific advantage of sharing keys remotely by use standard telecom components, thereby promoting cost-effective and high-performance metropolitan applications. Nevertheless, introduction high-rate spectrum broadening has pushed CVQKD from a single-mode to continuous-mode region, resulting in adoption modern digital signal processing (DSP) technologies recover quadrature information states. However, security proof DSP...
Magnetocardiography (MCG), which uses high-sensitivity magnetometers to record magnetic field signals generated by electrical activity in the heart, is a noninvasive method for evaluating heart diseases such as arrhythmia and ischemia. The MCG measurements usually require participant keeping still magnetically shielded room due immovable sensor noisy external environments. These requirements limit applications, exercise tests long-term observations, are useful early detections of diseases....
Quantum key distribution provides secure keys with information-theoretic security ensured by the principle of quantum mechanics. The continuous-variable version using coherent states offers advantages its compatibility telecom industry, e.g., commercial laser and homodyne detector, is now going through a booming period. In this review article, we describe system; focus on protocols based states, whose systems are gradually moving from proof-of-principle lab demonstrations to in-field...
We present a simple approach to realize truly random number generation based on measurement of the phase noise single mode vertical cavity surface emitting laser (VCSEL). The true randomness quantum originates from spontaneous emission photons and bit rate is ultimately limited only by linewidth. With final 20 Mbit/s, physically guaranteed sequence passes three standard tests. Moreover, for first time, {\it continuously} generated up 14 Gbit verified two additional criteria its randomness.
We show that the far-field beam spreading and direction of partially coherent Gaussian-Schell model (GSM) beams are independent on spatial coherence source through non-Kolmogorov atmospheric turbulence, which has potential applications in long-distance free-space optical communication. The effects coherence, exponent value alpha, inner scale outer turbulence studied details. GSM greater for smaller or bigger turbulent atmosphere.
In this paper, we consider a general bidirectional relay network with two sources and <i xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">N</i> relays when neither the source nodes nor know channel-state information (CSI). A joint relay-selection analog-network coding using differential modulation (RS-ANC-DM) is proposed. proposed scheme, employ modulations transmit modulated symbols to all at same time. The signal received superposition of...
A continuous-variable measurement-device-independent quantum key distribution (CV-MDI QKD) protocol using squeezed states is proposed where the two legitimate partners send Gaussian-modulated to an untrusted third party realize measurement. Security analysis shows that can not only defend all detector side channels, but also attain higher secret rates than coherent-state-based protocol. We present a method improve squeezed-state CV-MDI QKD by adding proper Gaussian noise reconciliation side....
Balanced homodyne detector (BHD) that can measure the field quadratures of coherent states has been widely used in a range quantum information technologies. Generally, BHD tends to suffer from narrow bands and an expanding bandwidth behavior usually traps into compromise with gain, electronic noise, classical noise ratio, etc. In this paper, we design construct wideband based on radio frequency integrated circuit technology. Our shows up 1.2 GHz its ratio is around 18 dB. Simultaneously,...
Abstract Ultralight bosons such as axion-like particles are viable candidates for dark matter. They can form stable, macroscopic field configurations in the of topological defects that could concentrate matter density into many distinct, compact spatial regions small compared with Galaxy but much larger than Earth. Here we report results search transient signals from domain walls by using global network optical magnetometers exotic (GNOME) physics searches. We data, consisting correlated...
The ideal use of small multilayer nets at the decision nodes a binary classification tree to extract nonlinear features is proposed. are trained and grown using gradient-type learning algorithm in multiclass case. method improves on standard design methods that it generally produces trees with lower error rates fewer nodes. It also reduces problems associated training large unstructured transfers problem selecting size net simpler finding right size. An efficient pruning proposed for this...
We demonstrate an external-cavity laser system using anti-reflection coated diode as gain medium with about 60 nm fluorescence spectrum, and a Rb Faraday anomalous dispersion optical filter (FADOF) frequency-selecting element transmission bandwidth of 1.3 GHz. With 6.4% feedback, single stable longitudinal mode is obtained linewidth 69 kHz. The wavelength this operating within the center highest peak FADOF over current range from 55 mA to 142 temperature 15 °C 35 °C, thus it immune...
Polarization spectroscopy in (4)He around 1083 nm is observed and optimized with a distributed feedback fiber laser applied for frequency stabilization. In order to improve the accuracy long-term stability of frequency-locking performance, power stabilization module added, dependences peak-to-peak amplitude difference (width) polarization signal on various pump probe powers are investigated.
Photon subtraction can enhance the performance of continuous-variable quantum key distribution (CV QKD). However, enhancement effect will be reduced by imperfections practical devices, especially limited efficiency a single-photon detector. In this paper, we propose non-Gaussian postselection method to emulate photon substraction used in coherent-state CV QKD protocols. The virtual not only avoid complexity and photon-subtraction operation, which extends secure transmission distance as ideal...
As a fundamental phenomenon in nature, randomness has wide range of applications the fields science and engineering. Among different types random number generators (RNG), quantum generator (QRNG) is kind promising RNG as it can provide provable true numbers based on inherent processes. Nevertheless, from QRNG be diminished (or even destroyed) if devices (especially entropy source devices) are not perfect or ill-characterized. To eliminate practical security loopholes source,...
The method of improving the performance continuous-variable quantum key distribution protocols by postselection has been recently proposed and verified. In measurement-device-independent (CV-MDI QKD) protocols, measurement results are obtained from untrusted third party Charlie. There is still not an effective CV-MDI QKD with measurement. We propose a to improve coherent-state protocol virtual photon subtraction via non-Gaussian postselection. transmitted data equivalent ideal on two-mode...
Can encrypted communication be secure at practical speeds? The authors propose a $r\phantom{\rule{0}{0ex}}a\phantom{\rule{0}{0ex}}t\phantom{\rule{0}{0ex}}e\phantom{\rule{0}{0ex}}l\phantom{\rule{0}{0ex}}e\phantom{\rule{0}{0ex}}s\phantom{\rule{0}{0ex}}s$...