Effect of Attenuation and Dispersion in the Communication Channel on the Secrecy of a Quantum Cryptosystem

The Secrecy Capacity of Practical Quantum Cryptography

Quantum cryptography has attracted much recent attention due to its potential for providing secret communications that cannot be decrypted by any amount of computational effort. This is the first analysis of the secrecy of a practical implementation of the BB84 protocol that simultaneously takes into account and presents the {\it full} set of complete analytical expressions for effects due to the presence of pulses containing multiple photons in the attenuated output of the laser, the finite length of individual blocks of key material, losses due to error correction, privacy amplification, con…

基于全被动光源的量子安全直接通信

Quantum secure direct communication based on fully passive source

针对主动调制引入侧信道的安全隐患，提出基于全被动光源的QSDC协议，通过被动调制量子态和诱骗态强度增强抵御侧信道攻击的鲁棒性，最大通信距离达16.875 km。

On Quantum Chosen-Ciphertext Attacks and Learning with Errors

Large-scale quantum computing is a significant threat to classical public-key cryptography. In strong "quantum access" security models, numerous symmetric-key cryptosystems are also vulnerable. We consider classical encryption in a model which grants the adversary quantum oracle access to encryption and decryption, but where the latter is restricted to non-adaptive (i.e., pre-challenge) queries only. We define this model formally using appropriate notions of ciphertext indistinguishability and semantic security (which are equivalent by standard arguments) and call it QCCA1 in analogy to the cl…

与参考帧无关的量子安全直接通信

Reference-frame-independent Quantum secure direct communication

本文提出一种与参考帧无关的量子安全直接通信协议，通过优化参考帧校准和信号强度，显著提升通信距离和保密容量。