Quantum random-number generator based on a photon-number-resolving detector

We demonstrated a high-efficiency quantum random number generator which takes inherent advantage of the photon number distribution randomness of a coherent light source. This scheme was realized by comparing the photon flux of consecutive pulses with a photon number resolving detector. The random bit generation rate could reach $2.4$ MHz with a system clock of $6.0$ MHz, corresponding to a random bit generation efficiency as high as $40\%$. The random number files passed all the stringent statistical tests.

Figure 1

Random number generation scheme based on photon statistics.

Figure 2

Random bit generation efficiency (${\eta }_R$) as a function of average detected photon number. Black straight line: with PNRD ($N=7$); red dashed line: with single-photon detector ($N=1$).

Figure 3

Configuration of the QRNG. LD: laser diode emitting at $850$ nm; Attn: optical intensity attenuator; ADC: analog-to-digital convertor with seven levels; Cmp: comparator. Inset: Color grading waveform of the APD response.

Figure 4

Bit autocorrelation as a function of bit distance.

Figure 5

Results of the STS 2.1.1 tests on $1000\times {10}^6$ bit patterns of binary bits.