## Ultrafast quantum random number generation based on quantum phase fluctuations |

Optics Express, Vol. 20, Issue 11, pp. 12366-12377 (2012)

http://dx.doi.org/10.1364/OE.20.012366

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### Abstract

A quantum random number generator (QRNG) can generate true randomness by exploiting the fundamental indeterminism of quantum mechanics. Most approaches to QRNG employ single-photon detection technologies and are limited in speed. Here, we experimentally demonstrate an ultrafast QRNG at a rate over 6 Gbits/s based on the quantum phase fluctuations of a laser operating near threshold. Moreover, we consider a potential adversary who has partial knowledge on the raw data and discuss how one can rigorously remove such partial knowledge with postprocessing. We quantify the quantum randomness through min-entropy by modeling our system and employ two randomness extractors - Trevisan’s extractor and Toeplitz-hashing - to distill the randomness, which is information-theoretically provable. The simplicity and high-speed of our experimental setup show the feasibility of a robust, low-cost, high-speed QRNG.

© 2012 OSA

**OCIS Codes**

(230.0230) Optical devices : Optical devices

(270.0270) Quantum optics : Quantum optics

(270.2500) Quantum optics : Fluctuations, relaxations, and noise

(060.5565) Fiber optics and optical communications : Quantum communications

(270.5568) Quantum optics : Quantum cryptography

**ToC Category:**

Quantum Optics

**History**

Original Manuscript: February 23, 2012

Revised Manuscript: May 4, 2012

Manuscript Accepted: May 6, 2012

Published: May 16, 2012

**Citation**

Feihu Xu, Bing Qi, Xiongfeng Ma, He Xu, Haoxuan Zheng, and Hoi-Kwong Lo, "Ultrafast quantum random number generation based on quantum phase fluctuations," Opt. Express **20**, 12366-12377 (2012)

http://www.opticsinfobase.org/oe/abstract.cfm?URI=oe-20-11-12366

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### References

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