CQI Research Group recently published a research paper on international journal Physical Review X, entitled Source-Independent Quantum Random Number Generation. The group proposed a new high-speed random number generator, which closes important loopholes in current random number generation and thus will have an impact on a wide range of applications of random numbers. The first author is IIIS PhD candidate Zhu Cao, with the corresponding author Assistant Prof. Xiongfeng Ma.

Figure : The measurement model (top) and photonic implementation (bottom) in the QRNG scheme. The whole photonic set-up consists of a laser source, a filter, a basis choice controller, a PBS and detectors. This setup can can reliably achieve a randomness generation rate exceeding 5 Kbits per second even when the laser source is uncharacterised.

Random numbers play an indispensable role in modern society in various areas of finance, cryptography, and computation. However, the source of randomness in such numbers is typically a problem in a physical random number generator: The “random” seeds are not truly random and can accordingly limit cryptographic security. Zhu Cao, together with the other authors, proposed a loss-tolerant, source-independent quantum random number generator whose output randomness can be certified even when the source is uncharacterized or untrusted. They also experimentally demonstrated the setup, and achieved a randomness generation rate exceeding 5 Kbits/s. This research effectively closed important loopholes in current random number generation and greatly improved the reliability of random number generation.

Physical Review X (PRX) is APS’s highly selective journal, covering all aspects of physics. The research was funded by the National Natural Science Foundation of China, with the experiment equipment support from QuantumCTeck Co., Ltd.

The full paper is available at:

http://journals.aps.org/prx/abstract/10.1103/PhysRevX.6.011020

(By Shuai Sun)