——Experimental Unconditionally Secure Bit Commitment
"This manuscript presents one of the first pioneer experiments on relativistic quantum bit commitment."This is how Physical Review Letters, the international authoritative journal of physics, remark the latest research results found by Prof. PAN Jianwei and his colleagues ZHANG Qiang and PENG Chengzhi. By matching the properties of quantum information and relativity theory, the team realized the unconditionally secure bit commitment for the first time in the world.
As online business, especially Internet finance develops rapidly, an increasing number of communicators like Internet terminals which do not trust each other need to communicate with each other more and more. And how to construct secure communication between different terminals becomes the prerequisite of steady development of Internet economy in the future.
Traditionally, quantum physics allows for unconditionally secure communication between parties that trust each other. However, when the parties do not trust each other such as in the bit commitment scenario, quantum physics is not enough to guarantee security unless extra assumptions are made.
Pan’s research team experimentally implement a quantum bit commitment protocol with relativistic constrains that offers unconditional security. The commitment is made through quantum measurements in two quantum key distribution systems in which the results are transmitted via fee-space optical communication to two agents separated with more than 20 km. The security of the protocol relies on the properties of quantum information and relativity theory.
The experiment provides unconditionally secure bit commitment between two mutually mistrustful partiesfor the first time. And it demonstrates that by combing quantum mechanics and relativity, a fundamental problem can be solved with practical applications. The inspiring results open a promising new research field with technological applications.
(TIAN Lin, USTC News Center)
