Experimental demonstration of multiparty quantum secret sharing and conference key agreement

Abstract

Quantum secret sharing (QSS) and conference key agreement (CKA) provide efficient encryption approaches for realizing multi-party secure communication, which are essential components of quantum networks. In this work, a practical, scalable, verifiable (k, n) threshold continuous variable QSS protocol secure against eavesdroppers and dishonest players are proposed and demonstrated. The protocol does not require preparing the laser source by each player and phase locking of independent lasers. The parameter evaluation and key extraction can be accomplished by only the dealer and the corresponding player. By using the multiple sideband modulation, a single heterodyne detector can extract the information of multiple players. The practical security of the system is considered. The system is versatile, it can support the CKA protocol by only modifying the classic post-processing and requiring no changes to the underlying hardware architecture. By implementing the QSS and CKA protocols with five parties over 25 km (55 km) single-mode fibers, a key rate of 0.0061 (7.14 × 10−4) bits per pulse is observed. The results significantly reduces the system complexity and paves the way for the practical applications of QSS and CKA with efficient utilization of resources and telecom technologies.

RQPoA: A random quantum PoA Consensus Mechanism in Blockchain Based on Quantum Methods

“…Quantum technology is developing rapidly, with an increasing number of quantum multi-party secret sharing protocols [9][10][11][12][13][14][15][16][17][18] based on QKD networks being proposed. These QSS protocols afford the secure and confidential sharing of a secret parameter among the validator nodes, which unrelated parties cannot access outside the list of validator nodes (LR).…”

“…In each consensus cycle, the leader node uses the VDF to obtain a random number R. Each candidate node, i.e., validator nodes that have not been granted the bookkeeping right in a consensus round, utilizes the unique random number and its ID to calculate the hash value for competing for the bookkeeping right. The highest hash value holder is elected as the leader node, and the leader node's identity is shared secretly among the validator nodes through a quantum multi-party secret sharing protocol [9][10][11][12][13][14][15][16][17][18]. After the election of the new leader node LN+1, LN+1 starts taking over the transaction queue from LN, LN+1 packages transactions to generate the next block.…”

Compact Quantum Random Number Generator Based on a Laser Diode and a Hybrid Chip with Integrated Silicon Photonics

“…Random numbers are key resources in the information age. They play an essential role in various applications, such as simulation, cryptography, and fundamental physical experiments [1][2][3][4][5][6][7][8][9][10]. A quantum random number generator (QRNG) can produce true random numbers with the characteristics of unpredictability, irreproducibility, and unbiasedness, guaranteed by the basic principles of quantum physics.…”

Low-loss integrated dynamic polarization controller based on silicon photonics

“…从上述研究中可以看 到, 器件耦合方式均采用垂直的二维光栅耦合方 式, 耦合损耗较大, 且静态消光比受二维光栅的限 制, 普遍低于30 dB. 较大的耦合损耗会使通信系 统探测效率降低, 特别是对损耗敏感的量子通信系 统 [6,9] ; 同时偏振消光比关系着动态偏振控制器对 偏振态的控制精度, 在量子通信领域对额外噪声和 安全密钥速率有着直接的影响 [16] . 如果能够优化 这两个核心参数值, 将会极大地提高硅基动态偏振 控制器的性能, 提升其应用价值和应用范围.…”