Progress in Quantum Electronics最新文献

Semiconductor nanowire lasers are single-element structures that can act as both gain material and cavity for optical lasing. They have typical dimensions on the order of an optical wavelength in diameter and several micrometres in length, presenting unique challenges for testing and characterisation. Optical microscopy and spectroscopy are powerful tools used to study nanowire lasers; here, we review the common techniques and analytical approaches often used and outline potential pitfalls in their application. We aim to outline best practise and experimental approaches used for characterisation of the material, cavity and lasing performance of nanowires towards applications in biology, photonics and telecommunications.

Pronounced polarization anisotropy in semiconductor nanowires has been exploited to achieve polarization-sensitive devices operating across the electromagnetic spectrum, from the ultraviolet to the terahertz band. This contribution describes the physical origins of optical and electrical anisotropy in nanowires. Polarization anisotropy arising from dielectric contrast, and the behaviour of (nano)wire grid polarizers, are derived from first principles. This review discusses experimental observations of polarization-sensitive light–matter interactions in nanowires. It then describes how these phenomena are employed in devices that detect or modulate polarized terahertz radiation on ultrafast timescales. Such novel terahertz device concepts are expected to find use in a wide variety of applications including high-speed terahertz-band communications and molecular fingerprinting.

In this review article, we discuss the molecular beam epitaxy and basic structural, electronic, optical, excitonic, chemical and catalytic properties of III-nitride nanostructures, including nanowires, monolayer heterostructures, and quantum dots. Their emerging applications in ultraviolet, visible and infrared photonics, quantum optoelectronics, and artificial photosynthesis that are relevant for next generation mobile display, virtual/augmented reality, quantum communication, and energy, water, and environment sustainability challenges are presented.

The ability to manipulate light at the level of single photons, its elementary excitation quanta, has recently made it possible to produce a rich variety of tailor-made quantum states and arbitrary quantum operations, of high interest for fundamental science and applications. Here we present a concise review of the progress made over the last few decades in the engineering of quantum light states. Although far from exhaustive, this review aims at providing a sufficiently wide and updated introduction that may serve as the entry point to such a fascinating and rapidly evolving field.

Quantum non-Gaussian states of photons and phonons are conclusive and direct witnesses of higher-than-quadratic nonlinearities in optical and mechanical processes. Moreover, they are proven resources for quantum sensing, communication and error correction with diverse continuous-variable systems. This review introduces theoretical analyses of nonclassical and quantum non-Gaussian states of photons and phonons. It recapitulates approaches used to derive operational criteria for photons tolerant to optical losses, their application in experiments and their nowadays extension to quantum non-Gaussian photon coincidences. It extends to a recent comparison of quantum non-Gaussianity, including robustness to thermal noise, and sensing capability for high-quality phononic Fock states of single trapped cooled ions. The review can stimulate further development in the criteria of quantum non-Gaussian states and experimental effort to prepare and detect such useful features, navigating the community to advanced quantum physics and technology.

The research on optical wireless communication (OWC) has been going on for more than two decades. Particularly, visible light communication (VLC), as a means of OWC combining communication with illumination, has been regarded as a promising indoor high-speed wireless approach for short-distance access. Recently, lightwave, millimeter-wave (mmWave), terahertz (THz) and other spectrum mediums are considered as potential candidates for beyond fifth-generation/sixth-generation (B5G/6G) mobile communication networks. On the basis of previous studies, this review focuses on revealing how the research of next-generation OWC technology should be carried out to meet the requirements of B5G/6G for practical deployment. The research, development and engineering transformation of the OWC systems are a paragon of interdisciplinary. It involves a wide discussion on how to build a high-speed, multi-user, full-duplex, white-light OWC system based on existing technologies by showing the innovations and trade-offs at various levels with material, device, air-interface technology, system and network architecture. The compatibility of OWC is emphasized and some advanced heterogeneous OWC systems are presented, which involves the combination or integration of various functions such as sensing, near-infrared (NIR) beam-steering, positioning and coexistence with radio frequency (RF) communication. Finally, several potential directions are pointed out for the actual engineering deployment in the B5G/6G era.

Semiconductor lasers are ubiquitous in modern science and technology for they are compact, fast, and efficient. They require relatively low power and thus are well suited for applications in the information technology. However, in conventional semiconductor lasers, the power required to reach the lasing threshold has a fundamental lower bound determined by the carrier density required to reach population inversion, or the transparency condition. This limitation can be overcome in a new type of laser, a polariton laser, which operates under a different mechanism. Coherent light emission from a polariton laser results from a polariton condensate, which is a coherent, thermodynamically favored many-body state, formed at a much lower carrier density than the population inversion density. Furthermore, since polaritons are matter-light hybrid modes formed via strong coupling between excitons and cavity photons, polariton lasers can be controlled via both the photon and exciton components, allowing greater flexibility in tuning and controlling the mode properties. These prospects have propelled intense research effort on polariton lasers in the past few decades. In this article, we will first review the essential properties of polaritons and polariton lasers, followed by recent developments on polariton lasers with unconventional properties and functionalities, and on new material platforms where room temperature polariton lasers have been demonstrated. We will conclude with a brief discussion on prospects of practical applications of polariton lasers.