Quantum random bit generation using stimulated Raman scattering

Abstract

Random number sequences are a critical resource in a wide variety of information systems, including applications in cryptography, simulation, and data sampling. We introduce a quantum random number generator based on the phase measurement of Stokes light generated by amplification of zero-point vacuum fluctuations using stimulated Raman scattering. This is an example of quantum noise amplification using the most noise-free process possible: near unitary quantum evolution. The use of phase offers robustness to classical pump noise and the ability to generate multiple bits per measurement. The Stokes light is generated with high intensity and as a result, fast detectors with high signal-to-noise ratios can be used for measurement, eliminating the need for single-photon sensitive devices. The demonstrated implementation uses optical phonons in bulk diamond.

Extracting the phase information from atomic memory by intensity correlation measurement

“…In future possible practical applications, some other materials are preferred. For example, diamond can provide larger bandwidth of the phase memory [26], and rare-earth-ion-doped crystal can provide longer memory time [27].…”

Nonclassical correlations between terahertz-bandwidth photons mediated by rotational quanta in hydrogen molecules

“…Example applications include single photon sources [1], cryptographic key generation [2], and the drive to implement optical quantum computing [3]. Nonlinear quantum optical phenomena are powerful tools for the development of such technologies: they enable the interaction of multiple photons, mediated by dipole coupling to levels in atomic, ionic, solid-state, and molecular systems.…”

Random number generation from spontaneous Raman scattering

“…If the source of randomness for a TRNG is quantum-mechanical the device is called a quantum random number generator (QRNG). Some examples of quantum optical measurements used for randomness generation include the timing of neutron emissions from radioactive material, 3,4 detection of a single photon at the output ports of a beam-splitter, 5-8 the phase or intensity of a nonlinear pulse in a stimulated Raman scattering (SRS) experiment [9][10][11] or laser 12 and photon number detection statistics. 13,14 Another source of quantum noise fluctuations is spontaneous Raman scattering (SpRS).…”

“…This discrete detection of SpRS single-photons, generated with random frequency, differs significantly compared to the SRS based QRNG demonstrations. [9][10][11] The SRS approaches rely on phase/intensity variations of a spontaneously initiated light beam amplified by stimulated Raman scattering with digital conversion of an analogue measurement required to generate a bit-string. Figure 2 outlines the experimental layout of the SpRS-QRNG.…”