Measurement-device-independent quantum key distribution (MDI-QKD) can remove all side-channel attacks on detectors. In the context of dramatic progress discrete-variable MDI-QKD and twin-field QKD, owing to critical challenge continuous-variable (CV) Bell-state measurement (BSM) two remote independent states, experimental demonstration CV-MDI-QKD over optical fiber has remained elusive. To solve this problem, a technology for CV-BSM states is developed that consists phase locking,...

We experimentally demonstrate a high-rate discretely modulated continuous-variable quantum key distribution over 80-km standard single-mode fiber with 2.5 Gbaud, 16-symbol, two-ring constellation. With the help of well-designed digital signal processing algorithms, excess noise system can be effectively suppressed. The achieved secret rates are 49.02 Mbits/s, 11.86 and 2.11 Mbits/s 25-km, 50-km, optical fiber, respectively, achieve 67.4%, 70.0%, 66.5% rate performance Gaussian-modulated...

Inflammatory bowel disease (IBD) is a serious digestive system disease, for which the clinical therapeutic choices remain limited. Dried fruits of Citrus aurantium L. (CAL) are traditional medicine used regulation system. The aim this study was to identify regulatory effects CAL on IBD and clarify mechanism active compounds. In trinitrobenzene sulfonic acid-induced rats, 125 500 mg/kg oral significantly alleviated weight loss diarrhea, decreased colitis inflammatory cell infiltration,...

Abstract Discrete-modulation continuous-variable (CV) quantum key distribution has the potential for large-scale deployment in secure communication networks owing to its low implementation complexity and compatibility with current coherent optical telecommunication. However, discrete-modulation protocols require relatively large constellation sizes achieve a rate comparable that of Gaussian modulation. Here, we show high modulation can be achieved using only ten or so states by implementing...

We experimentally demonstrated an all-fiber-based unidimensional continuous-variable quantum key distribution (CV QKD) protocol and analyzed its security under collective attack in realistic conditions. A pulsed balanced homodyne detector, which could not be accessed by eavesdroppers, with phase-insensitive efficiency electronic noise, was considered. Furthermore, a modulation method improved relative phase-locking technique one amplitude modulator phase were designed. The locked precisely...

Secure communication protocols based on quantum physics compel worldwide attention. Continuous-variable key distribution (CV-QKD) uses a cost-effective detection technique instead of dedicated single-photon-counting technology, and can provide high rates over metropolitan distances. Traditional coherent-state CV-QKD protocols, however, suffer from low tolerance channel excess noise. The authors succeed in distributing Einstein-Podolsky-Rosen entangled states 50-km standard fiber with...

Locking the sophisticated and expensive entanglement sources at shared relay node is a promising choice for building star-type quantum network with efficient use of resources, where involved parties only need to equip low-cost simple homodyne detectors. Here, our best knowledge, we demonstrate first experimental continuous variable key distribution an source between two users. We consider practical partially characterized entangled establish security analysis model protocol under realistic...

In continuous-variable (CV) quantum key distribution (QKD), the reconciliation efficiency and frame error rate of information have a significant impact on secret rate. For fixed-rate multiedge-type low-density parity-check (LDPC) code, will inevitably vary due to fluctuations signal-to-noise ratio (SNR) CV QKD system, which degrades performance system. We propose high-efficiency rate-adaptive scheme by combining raptorlike (RL) LDPC codes with addition trusted noises. establish model adding...

We propose and demonstrate a new scheme of high-efficiency generation the three-photon polarization-entangled W state, which is typical three-qubit entangled state. The high efficiency has enabled first full characterization state by quantum tomography. have analyzed obtained observed its nature tripartite entanglement robustness entanglement.

In continuous-variable quantum key distribution, the loss and excess noise of channel are parameters that determine secure rate maximal distribution distance. We investigate imperfect state preparation in Gaussian modulation coherent-state protocol both theoretically experimentally. show characteristic prepared states phase space is broken due to incorrect calibration working for amplitude modulator modulator. This further causes a significant increase misestimate loss. To ensure an accurate...

Quantum key distribution enables unconditionally secure between two legitimate users. The information-theoretic security is guaranteed by the fundamental laws of quantum physics. Initially, protocol was proposed based on qubits. Later on, it found that continuous variables can also be exploited for this target. variable build upon standard telecommunication technology and exhibits a higher secret rate per pulse at relatively short distance due to possibility encoding more than 1 bit pulse....

In a continuous-variable quantum key distribution (CV-QKD) system, the computation speed of post-processing procedure, including information reconciliation (IR) and privacy amplification (PA), inevitably affects practical secret rate. IR PA can be implemented in parallel using low-density parity-check (LDPC) codes hash functions, respectively. We achieve high-speed hardware-accelerated procedure for Gaussian symbols on field-programmable gate array (FPGA) by taking advantage its superior...

In a commercial fiber-based quantum key distribution (QKD) system, the state of polarization (SOP) optical fields is inevitably disturbed by random birefringence standard single-mode fiber due to an external complex environment. We analyze theoretically effect SOP fluctuations on continuous-variable (CV) QKD system and experimentally verify its validity. To overcome influence variations, self-adaptive gradient algorithm proposed achieve high-speed controlling under pulsed light with field...

Large Language Models (LLMs) (e.g., ChatGPT) have shown impressive performance in code generation. LLMs take prompts as inputs, and Chain-of-Thought (CoT) prompting is the state-of-the-art technique. CoT asks first to generate CoTs (i.e., intermediate natural language reasoning steps) then output code. However, designed for generation has low accuracy In this paper, we propose Structured (SCoTs) present a novel technique generation, named SCoT prompting. Our motivation source contains rich...

Abstract Quantum key distribution (QKD) can provide information-theoretically secure keys for two parties of legitimate communication, and information reconciliation, as an indispensable component QKD systems, correct errors present in raw based on error-correcting codes. In this paper, we first describe the basic knowledge reconciliation its impact continuous variable QKD. Then introduce schemes corresponding error correction codes employed. Next, rate-compatible codes, hardware...

Cascaded phase shifters (CPSs) based on silicon photonics integrated chips play important roles in quantum information processing tasks. Owing to an increase the scale of chips, time required calibrate various CPSs has increased. We propose a pairwise scan method for rapidly calibrating by introducing equivalent Mach Zehnder Interferometer structures and reasonable constraint initial relative phase. The calibration can be nearly completed when scanning process is finished, only little...

We propose two interesting methods of generating the four-photon $W$ state. These use parametric down-conversion processes, linear optical elements, and commercial photon detectors, which are readily feasible under current technology. They can also be used to generate three-photon state, Greenberger-Horne-Zeilinger maximally entangled photon-number state (a typical entanglement state) by simply changing some experimental components or their parameters. Moreover, assuming we have...

The measurement-device-independent quantum key distribution (MDI-QKD) protocol is immune to imperfect measurement devices. However, its practicality and performance when implemented in continuous-variable (CV) mode are still not satisfactory. We propose a CV-MDI-QKD based on modulated squeezed states, analyze security against two-mode Gaussian attack. results show that the can achieve higher secret rate transmission distance than previous coherent-state squeezed-state protocols. A method...