Improving the efficiency of quantum hash function by dense coding of coin operators in discrete-time quantum walk

• 来源期刊: 中国科学:物理学 力学 天文学（英文版）
• 年，卷（期）: 2018,（3）
• 页码范围: 18-25
• 页数: 8页
• 语种: 英文

摘要

Li et al.first proposed a quantum hash function (QHF) in a quantum-walk architecture.In their scheme,two two-particle interactions,i.e.,I interaction and π-phase interaction are introduced and the choice ofIor π-phase interactions at each iteration depends on a message bit.In this paper,we propose an efficient QHF by dense coding of coin operators in discrete-time quantum walk.Compared with existing QHFs,our protocol has the following advantages:the efficiency of the QHF can be doubled and even more;only one particle is enough and two-particle interactions are unnecessary so that quantum resources are saved.It is a clue to apply the dense coding technique to quantum cryptographic protocols,especially to the applications with restricted quantum resources.