In mathematics and computer science, random numbers have the role of a resource for assisting proofs, making cryptography secure, and enabling computational protocols. This role motivates efforts to produce random numbers as a physical process. Potential physical sources abound, but arguably the most fundamental are those based on elementary quantum mechanical processes. This review discusses the current status of devices that generate quantum random numbers.

Quantum random number generators

During the past few years, metasurfaces have been used to demonstrate optical elements and systems with capabilities that surpass those of conventional diffractive optics. Here, we review some of these recent developments, with a focus on dielectric structures for shaping optical wavefronts. We discuss the mechanisms for achieving steep phase gradients with high efficiency, simultaneous polarization and phase control, controlling the chromatic dispersion, and controlling the angular response. Then, we review applications in imaging, conformal optics, tunable devices, and optical systems. We conclude with an outlook on future potentials and challenges that need to be overcome.

https://www.degruyter.com/document/doi/10.1515/nanoph-2017-0129/pdf

A review of dielectric optical metasurfaces for wavefront control

2D Layered Materials: Synthesis, Nonlinear Optical Properties, and Device Applications

Abstract The emergence of silicon photonics over the past two decades has established silicon as a preferred substrate platform for photonic integration. While most silicon-based photonic components have so far been realized in the near-infrared (near-IR) telecommunication bands, the mid-infrared (mid-IR, 2–20-μm wavelength) band presents a significant growth opportunity for integrated photonics. In this review, we offer our perspective on the burgeoning field of mid-IR integrated photonics on silicon. A comprehensive survey on the state-of-the-art of key photonic devices such as waveguides, light sources, modulators, and detectors is presented. Furthermore, on-chip spectroscopic chemical sensing is quantitatively analyzed as an example of mid-IR photonic system integration based on these basic building blocks, and the constituent component choices are discussed and contrasted in the context of system performance and integration technologies.

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Mid-infrared integrated photonics on silicon: a perspective

In the past several years, two-dimensional black phosphorus (BP) has captured the research community's interest because of its unique electronic, photonic, and mechanical properties. Remarkable efforts have been made regarding the synthesis, fundamental understanding, and applications of BP in the fields of nanoelectronics, nanophotonics, and optoelectronics. In this review, we summarize the recent developments in the study of BP, which covers the state-of-the-art synthesis methods for preparing single-layer or few-layer BP, the recent advances in characterizing its electronic, optical and mechanical properties, and the reported functional devices utilizing such properties. Finally we discuss the existing challenges in developing BP-based nanoelectronics and optoelectronics, and describe the prospects for future BP-related research.

Recent advances in black phosphorus-based photonics, electronics, sensors and energy devices

We present a high-quality bias-free quantum random number generator (QRNG) using photon arrival time selectively, in accordance with the number of photon detection events within a sampling time interval in attenuated light. It is well shown in both theoretical analysis and experimental verification that this random number production method eliminates both bias and correlation perfectly without more postprocessing and that the random number can clearly pass the standard randomness tests. We fulfill theoretical analysis and experimental verification of the method whose rate can reach up to 45 Mb/s.

A Bias-Free Quantum Random Number Generation Using Photon Arrival Time Selectively

We present a high-quality quantum random number generator (QRNG) without posting processing using photon arrival time selectively in accordance with the number of photon detection events within a sampling time interval in attenuated light. It is well showed in both theoretical analysis and experiments verification that this random number production method eliminates both bias and correlation perfectly without post processing and the random number can be clearly passed the standard randomness tests. We fulfill theoretical analyses and experimental verification of the method whose rate can reach up to 45Mbps.

Quantum random number generation using photon arrival time selectively without post-processing.

The invention discloses a generating method and device for a quantum random number. The device comprises a quantum random number source and a random number sampler. The quantum random number source is used for outputting a weak optical detection signal. The random number sampler is used for amplifying and screening the weak optical detection signal and then dividing the weak optical detection signal into a signal A and a signal B. Time measuring is performed on the signal A, and counting is performed on the signal B. Within a fixed period, the count of the signal B is sampled, and when the count value is one, a measured time quantized value of the signal A serves as the random number. According to the device, the quality of the generated random number is high, the generating speed is high, and post-processing is not needed.

Tian-yu Xie

Papers

A Bias-Free Quantum Random Number Generation Using Photon Arrival Time Selectively

Quantum random number generation using photon arrival time selectively without post-processing.

Generating method and device for quantum random number