Electronics and Telecommunications Research Institute, Daejeon 305-700, Korea.
Phys Rev Lett. 2009 Dec 4;103(23):230501. doi: 10.1103/PhysRevLett.103.230501. Epub 2009 Dec 1.
Quantum cryptography allows one to distribute a secret key between two remote parties using the fundamental principles of quantum mechanics. The well-known established paradigm for the quantum key distribution relies on the actual transmission of signal particle through a quantum channel. In this Letter, we show that the task of a secret key distribution can be accomplished even though a particle carrying secret information is not in fact transmitted through the quantum channel. The proposed protocols can be implemented with current technologies and provide practical security advantages by eliminating the possibility that an eavesdropper can directly access the entire quantum system of each signal particle.
量子密码学利用量子力学的基本原理在两个远程方之间分配秘密密钥。量子密钥分发的著名既定范例依赖于信号粒子通过量子通道的实际传输。在这封信中，我们表明，即使实际上并未通过量子通道传输携带秘密信息的粒子，也可以完成秘密密钥分发的任务。所提出的协议可以使用当前技术实现，并通过消除窃听者可以直接访问每个信号粒子的整个量子系统的可能性，提供实际的安全优势。
