Real-time high-speed mutually independent two-channel quantum random number generator (QRNG) device has been proposed using a programmable photonic integrated circuit in silicon photonics platform. Broadband random fluctuations of quantum photonic waveguide vacuum mode is harnessed in each of the mutually independent channels by mixing a guided coherent laser light operating at λ ∼ 1550 nm. All classical noises arising out of electrical, mechanical, thermal disturbances, etc. are minimized by the use of homodyne detection and appropriate programming of the photonic integrated circuit. The method of classical noise elimination has been supported with an appropriate theoretical modeling and experimental observations. The raw random number generation rate per channel was 4 Gbps, when the output signal from the homodyne detectors (bandwidth 1.6 GHz) was sampled at 500 MSa/s and subsequently digitized by a 14-bit analog-to-digital converter. We have also shown that the proposed PPIC design can be scaled up to higher number of channels using CMOS fabrication process compatible silicon photonics technology. Such mutually independent multi-channel QRNG sources are especially useful for high-speed chip-scale quantum key distribution (QKD) transceivers.
Real-time high-speed mutually independent two-channel quantum random number generator (QRNG) device has been proposed using a programmable photonic integrated circuit in silicon photonics platform. Broadband random fluctuations of quantum photonic waveguide vacuum mode is harnessed in each of the mutually independent channels by mixing a guided coherent laser light operating at λ ∼ 1550 nm. All classical noises arising out of electrical, mechanical, thermal disturbances, etc. are minimized by the use of homodyne detection and appropriate programming of the photonic integrated circuit. The method of classical noise elimination has been supported with an appropriate theoretical modeling and experimental observations. The raw random number generation rate per channel was 4 Gbps, when the output signal from the homodyne detectors (bandwidth 1.6 GHz) was sampled at 500 MSa/s and subsequently digitized by a 14-bit analog-to-digital converter. We have also shown that the proposed PPIC design can be scaled up to higher number of channels using CMOS fabrication process compatible silicon photonics technology. Such mutually independent multi-channel QRNG sources are especially useful for high-speed chip-scale quantum key distribution (QKD) transceivers.
Real-time high-speed mutually independent two-channel quantum random number generator (QRNG) device has been proposed using a programmable photonic integrated circuit in silicon photonics platform. Broadband random fluctuations of quantum photonic waveguide vacuum mode is harnessed in each of the mutually independent channels by mixing a guided coherent laser light operating at λ ∼ 1550 nm. All classical noises arising out of electrical, mechanical, thermal disturbances, etc. are minimized by the use of homodyne detection and appropriate programming of the photonic integrated circuit. The method of classical noise elimination has been supported with an appropriate theoretical modeling and experimental observations. The raw random number generation rate per channel was 4 Gbps, when the output signal from the homodyne detectors (bandwidth 1.6 GHz) was sampled at 500 MSa/s and subsequently digitized by a 14-bit analog-to-digital converter. We have also shown that the proposed PPIC design can be scaled up to higher number of channels using CMOS fabrication process compatible silicon photonics technology. Such mutually independent multi-channel QRNG sources are especially useful for high-speed chip-scale quantum key distribution (QKD) transceivers.
Quantum random number generator (QRNG) allows for the production of truly unpredictable random numbers, thanks to the inherent randomness available in quantum mechanics. However, its practical implementation is facing several challenges, including the practical security loophole, high-speed real-time randomness extraction, and large-scale production. In this work, we address these challenges with a chip-based, source-independent quantum random number generator achieving 20 Gbps real-time generation rate. It ensures the practical security through a source-independent security framework and the modeling of measurement devices. A bandwidth exceeding 2 GHz and a clearance reaching 10 dB is achieved by a silicon-based homodyne detector. Analog-to-digital conversion and randomness extraction are integrated on a single data collection and processing board, where the optimized parallel randomness extraction algorithm on a field programmable gate array achieves a throughput up to 28 Gbps. The results promise a high-speed and practically secure quantum random number generation on a chip, paving the way for its large-scale deployments and widespread applications.
Quantum random number generators (QRNGs) can produce true random numbers. Yet, the two most important QRNG parameters highly desired for practical applications, i.e., speed and size, have to be compromised during implementations. Here, we present the fastest and miniaturized QRNG with a record real-time output rate as high as 18.8 Gbps by combining a photonic integrated chip and the technology of optimized randomness extraction. We assemble the photonic integrated circuit designed for vacuum state QRNG implementation, an InGaAs homodyne detector, and a high-bandwidth transimpedance amplifier into a single chip using hybrid packaging, which exhibits the excellent characteristics of integration and high-frequency response. With a sample rate of 2.5 GSa/s in a 10-bit analog-to-digital converter and subsequent paralleled postprocessing in a field programmable gate array, the QRNG outputs ultrafast random bitstreams via a fiber optic transceiver, whose real-time speed is validated in a personal computer.
Recent advancements in integrated photonics have shown great promise for the serial production of chip-scale quantum random number generators (QRNG). Considerable progress has been made towards developing fully on-chip QRNGs that exploit the interference of phase-randomized fields from two independent lasers. While a common alternative design, based on a single laser and interferometer, would further improve power consumption and ease of operation, monolithic integration of such a design has thus far faced challenges, including high losses and crosstalk. We solve these key challenges and report fast single-laser interferometric QRNGs integrated onto monolithic chips. By combining on-chip optical amplification with electronic common-mode rejection techniques, our photonic integrated circuits (PICs) stably convert the spontaneous emission phase noise of a diode laser into electronic pulses of high-contrast random intensity at GHz clock rates. Using real-time, hash-function-based randomness extraction, uniformly distributed, truly unpredictable random numbers are generated at a rate of 3 Gbps.
Abstract We present a high-speed continuous-variable quantum random number generator (QRNG) based on heterodyne detection of vacuum fluctuations. The scheme follows a source-device-independent security model in which the entropy originates from quantum measurement uncertainty and no model of the source is required; security depends only on the trusted measurement device and the calibrated discretization, and thus remains valid even under adversarial state preparation. The optical field is split by a 90 ∘ optical hybrid and measured by two balanced photodiodes to obtain both quadratures of the vacuum state simultaneously. The analog outputs are digitized using a dual-channel 12-bit analog-to-digital converter operating at a sampling rate of 3.2 GS s −1 per channel, and processed in real time by an field-programmable gate array (FPGA) implementing Toeplitz hashing for randomness extraction. The quantum-to-classical noise ratio was verified through calibrated power spectral density measurements and cross-checked in the time domain, confirming vacuum-noise dominance within the 1.6 GHz detection bandwidth. After extraction, the system achieves a sustained generation rate of R net = 33.92 Gbit s − 1 of uniformly distributed random bits, which pass all NIST and Dieharder statistical tests. The demonstrated platform provides a compact, FPGA-based realization of a practical heterodyne continuous-variable source-independent QRNG suitable for high-rate quantum communication and secure key distribution systems.
Random numbers find applications in a range of different fields, from quantum key distribution and classical cryptography to fundamental science.They also find extensive use in gambling and lotteries.By exploiting the probabilistic nature of Quantum Mechanics, quantum random number generators (QRNGs) provide a secure and efficient means to produce random numbers.Most of the quantum random number generators demonstrated so far have been built in bulk optics, either using free space or fibre-optic components.While showing good performance, most of these demonstrations are strongly limited in real life applications, due to issues such as size, costs and the manufacturing process.In this thesis I report the demonstration of three different QRNGs based on integrated photonics.First, I demonstrated a QRNG based on homodyne measurement of optical vacuum states on a Silicon-on-insulator (SOI) chip.Second, I developed a SOI QRNG based on phase fluctuations from a laser diode.In these two schemes all the optical and opto-electronic components, excluding the laser, were integrated onto a silicon-on-insulator device.These schemes, being built on a silicon-on-insulator chip are potentially CMOS compatible and pave the way for being integrated onto other more complex systems.These QRNGs showed Gbps generation rates and passed the statistical tests provided by NIST.Third, I report the preliminary study of a QRNG based on homodyne measurement of optical vacuum states onto a Indium Phosphide (InP) chip.In this third experiment, all the components, including a laser diode, were monolithically integrated in the same chip, which provide a great advantage in terms of the overall size of the optics of the device.First, I would like to thank Jonathan, for the opportunity to pursue my PhD and for guiding my research in these four years.Thank you for giving me the chance to follow my curiosity and for pushing me to get the best out of my research.Thank you, Dylan, for being so helpful, always ready to answer my questions.I would like to thank Giacomo for sharing a big part of my research in these years