Abstract-Comparison of Terahertz, Microwave, and Laser Power Beaming Under Clear and Adverse Weather Conditions

Lou Rizzo, John F. Federici, Samuel Gatley, Ian Gatley, James L. Zunino,  Kate J. Duncan

https://link.springer.com/article/10.1007/s10762-020-00719-w

Wireless transmission of power from point to point has been developed in two predominate electromagnetic frequency ranges: near-infrared and microwave. In this paper, the prospect of wireless power beaming in the terahertz frequency range is explored with emphasis on the role of adverse weather. Link distance, power transmission, and safety performance of near-infrared, microwave, and terahertz power beaming are compared under clear and adverse weather conditions. While infrared power beaming provides the longest link distances of the three under clear weather conditions, terahertz power beaming can provide better performance under adverse weather conditions.

Abstract-Terahertz Van Atta Retroreflecting Arrays

Dhruvkumar Desai, Ian Gatley, Christopher Bolton, Lou Rizzo, Samuel Gatley,  John F. Federici

https://link.springer.com/article/10.1007/s10762-020-00721-2

As an initial step in developing steerable mirrors for terahertz (THz) wireless communication systems, this paper describes the development of a passive planar terahertz retroreflectors based on the Van Atta array. The retroreflector is optimized and simulated using finite-element modeling (FEM) software, fabricated via a low-cost additive manufacturing method, and characterized using THz time-domain spectroscopy. Comparison to a flat metal plate shows a significant increase in retroreflectivity for off-normal angles of incidence.

Abstract-Terahertz quantum cryptography

Carlo Ottaviani, Matthew J. Woolley, Misha Erementchouk, John F. Federici, Pinaki Mazumder, Stefano Pirandola, Christian Weedbrook

https://arxiv.org/abs/1805.03514

A well-known empirical rule for the demand of wireless communication systems is that of Edholm's law of bandwidth. It states that the demand for bandwidth in wireless short-range communications doubles every 18 months. With the growing demand for bandwidth and the decreasing cell size of wireless systems, terahertz (THz) communication systems are expected to become increasingly important in modern day applications. With this expectation comes the need for protecting users' privacy and security in the best way possible. With that in mind, we show that quantum key distribution can operate in the THz regime and we derive the relevant secret key rates against realistic collective attacks. In the extended THz range (from 0.1 to 50 THz), we find that below 1 THz, the main detrimental factor is thermal noise, while at higher frequencies it is atmospheric absorption. Our results show that high-rate THz quantum cryptography is possible over distances varying from a few meters using direct reconciliation, to about 220m via reverse reconciliation. We also give a specific example of the physical hardware and architecture that could be used to realize our THz quantum key distribution scheme.