High-speed quantum-random number generation by continuous measurement of arrival time of photons

Abstract

We demonstrate a novel high speed and multi-bit optical quantum random number generator by continuously measuring arrival time of photons with a common starting point. To obtain the unbiased and post-processing free random bits, the measured photon arrival time is converted into the sum of integral multiple of a fixed period and a phase time. Theoretical and experimental results show that the phase time is an independent and uniform random variable. A random bit extraction method by encoding the phase time is proposed. An experimental setup has been built and the unbiased random bit generation rate could reach 128 Mb/s, with random bit generation efficiency of 8 bits per detected photon. The random numbers passed all tests in the statistical test suite.

Single-Photon Reflectivity and Depth Imaging by Continuous Measurement of Arrival Time of Photons

“…Instead, it is reflected into a fiber optic coupler and then enter the SPAD detector. After receiving the echo optical signals, the SPAD detector exports a discrete single-photon pulse sequence, that is, photon arrival timing signal [29], to the FPGA control module and the start input of TCSPC module, and each pulse represents a detected photon. The laser pulse sync signal is input to the FPGA control module and the stop input of TCSPC module.…”

Recommendations and illustrations for the evaluation of photonic random number generators

“…The h( , τ ) analysis is not limited to continuous time series; it can also be applied to physical entropy sources based on discrete events such as single photon detection. For example, entropy sources using single photon time-of-arrival measurements [8,9,11] can be analyzed by considering the entropy rate as a function of the temporal precision ( ) of the measurement of the arrival times and of the maximum count rate (τ −1 ), as we show in the section 2.1 Despite these important advantages, the h( , τ ) analysis has only recently been applied in the context of physical random number generation [53]. The RNG system in ref.…”

“…If the average photon interarrival time is much less than the detector dead time, n will be a random variable that follows the Poisson distribution [34]. It turns out that this technique has the same rate of entropy production as the one we focus on here: single photon time-of-arrival measurements [8,9,11]. photons per second.…”

“…The fundamental randomness of quantum mechanics present in many optical systems can be employed to generate true random numbers. In some optical entropy sources such as single photon measurements [2,[8][9][10][11], optical parametric oscillators [12], and spontaneous Raman scattering [13], the measurements themselves are quantized. In others, such as those based on amplified spontaneous emission [3,[14][15][16][17][18][19][20], laser phase noise [21][22][23][24][25][26], quantum vacuum fluctuations [27][28][29][30][31], and stimulated Raman scattering [32,33], an unpredictable analog waveform with quantum mechanical origins is sampled and digitized.…”

“…Due to the increasing importance of the security of digital information and the wide variety of physical methods used to generate random numbers, a standard set of evaluation metrics for random number generation is essential. Previous works have used a variety of methods to estimate the entropy of physical sources of randomness [8][9][10][11]19,23,[25][26][27][40][41][42]44,45,50]; however, many of these techniques assume that there are no inter-sample correlations. As of this writing, there is no widely accepted technique to estimate the entropy of physical entropy sources.…”