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Bounds on the frequency domain behavior of electrically small antennas are adapted to assess the time domain distortion or fidelity achievable by simple linear time-invariant (LTI) systems. Rigorous expressions for a TM$_{01}$ spherical…

Applied Physics · Physics 2023-07-19 Kurt Schab , Amritpal Singh , Nicole Bohannon

The spatial degrees of freedom (DoFs) greatly increase in the near-field region of millimeter wave or terahertz multiple-input multiple-output communications with extremely large antenna arrays (XL-MIMO). To employ the increased spatial…

Information Theory · Computer Science 2023-05-18 Shuaishuai Guo , Kaiqian Qu

Modulation of metasurfaces in time gives rise to several exotic space-time scattering phenomena by violating the reciprocity and generation of higher-order frequency harmonics. We introduce a new design paradigm for time-modulated…

Applied Physics · Physics 2018-12-31 Mohammad Mahdi Salary , Samad Jafar-Zanjani , Hossein Mosallaei

Reconfigurable multiple-input multiple-output can provide performance gains over traditional MIMO by reshaping the channels, i.e., introducing more channel realizations. In this paper, we focus on the achievable rate maximization pattern…

Information Theory · Computer Science 2023-02-14 Haonan Wang , Ang Li , Ya-Feng Liu , Qibo Qin , Lingyang Song , Yonghui Li

The use of large-scale antenna arrays can bring substantial improvements in energy and/or spectral efficiency to wireless systems due to the greatly improved spatial resolution and array gain. Recent works in the field of massive…

Information Theory · Computer Science 2014-12-10 Emil Björnson , Jakob Hoydis , Marios Kountouris , Mérouane Debbah

This paper investigates the fundamental limits on the target detection performance with a dual-function multiple-input-multiple-output (MIMO) radar communication (RadCom) systems. By assuming the presence of a point-like target and a…

Information Theory · Computer Science 2022-04-12 Bo Tang , Zhongrui Huang , Lilong Qin , Hai Wang

The concepts of many optical devices are based on the fundamental physical phenomena such as resonances. One of the commonly used devices is an electromagnetic antenna that converts localized energy into freely propagating radiation and…

Achieving non-reciprocity and building nonreciprocal components through spatio-temporal modulation of material properties has attracted a lot of attention in the recent past as an alternative to the more traditional approach of exploiting…

Applied Physics · Physics 2018-10-31 Negar Reiskarimian , Aravind Nagulu , Tolga Dinc , Harish Krishnaswamy

Closely-spaced quantum emitters coherently sharing excitation can release their energy faster than suggested by a simple sum over their individual emission rates - a phenomenon known as superradiance. Here, we show that the assumption of…

Quantum Physics · Physics 2019-12-13 Severin Bang , Stefan Yoshi Buhmann , Robert Bennett

Electrical and electronic systems can be disturbed by radiation-induced effects. In some cases, radiation-induced effects are of a low probability and can be ignored; however, radiation effects must be considered when designing systems that…

Accelerator Physics · Physics 2016-07-07 B. Todd , S. Uznanski

Movable antennas represent an emerging field in telecommunication research and a potential approach to achieving higher data rates in multiple-input multiple-output (MIMO) communications when the total number of antennas is limited. Most…

Information Theory · Computer Science 2025-06-03 Amna Irshad , Emil Björnson , Alva Kosasih , Vitaly Petrov

The resonant quantum dynamics of an excited two-level emitter is investigated via classical modulation of its transition frequency while simultaneously the radiator interacts with a broadband electromagnetic field reservoir. The frequency…

Quantum Physics · Physics 2015-06-23 Mihai Macovei , Christoph H. Keitel

We experimentally demonstrate a Purcell effect-based design technique for improved impedance matching, and thus enhanced radiation efficiency from a small microwave emitter. Using an iterative process centred on comparing the phase of the…

Applied Physics · Physics 2022-09-29 L. D. Stanfield , A. W. Powell , S. A. R. Horsley , J. R. Sambles , A. P. Hibbins

The problem of electromagnetic emission generation in plasma with electron beams is relevant both for practical applications and for interpretation of radio emission processes in astrophysical systems. In this work, we consider the case of…

Plasma Physics · Physics 2023-08-08 Vladimir Annenkov , Evgeniia Volchok , Igor Timofeev

The present work deals with a theoretical research on the emission and radiation properties of a dipole emitter source close to a dimer graphene plasmonic antenna. Modification of the radiation and the quantum efficiencies resulting from…

Optics · Physics 2018-10-17 Mauro Cuevas

With the continued scaling of microelectronic devices along with the growing demand of high-speed wireless telecommunications technologies, there is increasing need for high-frequency device modeling techniques that accurately capture the…

Mesoscale and Nanoscale Physics · Physics 2018-05-29 Timothy M. Philip , Matthew J. Gilbert

The central design challenge in next generation wireless systems is to have these systems operate at high bandwidths and provide high data rates while being cognizant of the energy consumption levels especially in mobile applications. Since…

Information Theory · Computer Science 2016-11-15 Mustafa Cenk Gursoy

We evaluate the advantages of performing cross-phase modulation (XPM) on a very-far-off-resonance atomic system. We consider a ladder system with a weak (few-photon level) control coherent field imparting a conditional nonlinear phase shift…

Quantum Physics · Physics 2016-10-26 Julián Martínez-Rincón , John C. Howell

Radio over Fiber (RoF) Systems exploiting a direct modulation of the laser source are presently utilized within important Radioastronomic scenarios. Due to the particular operating conditions of some of these realizations, the phenomena…

Instrumentation and Methods for Astrophysics · Physics 2023-07-19 Jacopo Nanni , Andrea Giovannini , Muhammad Usman Hadi , Enrico Lenzi , Simone Rusticelli , Randall Wayth , Federico Perini , Jader Monari , Giovanni Tartarini

We consider the spontaneous emission of a two-level quantum emitter, such as an atom or a quantum dot, in a modulated time-dependent environment with a photonic band gap. An example of such an environment is a dynamical photonic crystal or…

Quantum Physics · Physics 2017-08-08 Giuseppe Calajò , Lucia Rizzuto , Roberto Passante