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This paper presents the efficient Yagi-Uda nanoantenna with the chain of directors, reflector and a feed element, where these elements have been optimized to fulfil the requirement of high directivity and the gain of antenna. The proposed…

Applied Physics · Physics 2019-06-05 Vishal K. Doltani , Fahim A Umrani , Riaz A. Soomro

In an in-band full-duplex system, radios transmit and receive simultaneously in the same frequency band at the same time, providing a radical improvement in spectral efficiency over a half-duplex system. However, in order to design such a…

We demonstrate an on-demand source of microwave single photons with 71--99\% intrinsic quantum efficiency. The source is narrowband (300\unite{kHz}) and tuneable over a 600 MHz range around 5.2 GHz. Such a device is an important element in…

Starting from a new factorization of the frequencydomain modal expansion coefficients, we generate analytical expressions in time-domain for the various quantities of interest of a biconical antenna of arbitrary length and cone angle. In…

Classical Physics · Physics 2023-08-16 Ramakrishna Janaswamy

In Nature Photonics 5, 166 (2011), we reported on a planar dielectric antenna that achieved 96% efficiency in collecting the photons emitted by a single molecule. In that work the transition dipole moment of the molecule was set…

Quantum Physics · Physics 2016-04-13 Xue-Wen Chen , Stephan Goetzinger , Vahid Sandoghdar

Spontaneous emission of quantum emitters can be modified by engineering their optical environment. This allows a resonant nanoantenna to significantly modify the radiative properties of a quantum emitter. In this article, we go beyond the…

We devise new optical antennas that reduce the excited-state radiative lifetimes of emitters to the order of 100 femtoseconds while maintaining quantum efficiencies of about 80% at a broadband operation. Here, we combine metallic…

Optics · Physics 2015-06-05 Xue-Wen Chen , Mario Agio , Vahid Sandoghdar

Biconical-type antennas featuring high directivity have been designed, created, and tested in anechoic chamber. Results in the range between 1 and 5 GHz are presented in this article. In particular, two different configurations have been…

Applied Physics · Physics 2022-02-07 Daniele Funaro , Alessandro Chiolerio

Optical driving of materials has emerged as a versatile tool to control their properties, with photo-induced superconductivity being among the most fascinating examples. In this work, we show that light or lattice vibrations coupled to an…

Dense arrays can facilitate the integration of multiple antennas into finite volumes. In addition to the compact size, sub-wavelength spacing enables superdirectivity for endfire operation, a phenomenon that has been mainly studied for…

Information Theory · Computer Science 2022-08-03 Konstantinos Dovelos , Stylianos D. Assimonis , Hien Quoc Ngo , Michail Matthaiou

A simple experiment is presented which indicates that electromagnetic fields propagate superluminally in the near-field next to an oscillating electric dipole source. A high frequency 437MHz, 2 watt sinusoidal electrical signal is…

General Physics · Physics 2007-05-23 William D. Walker

An ensemble of resonators arranged on a sub-wavelength scale is usually considered as a bulk effective medium, known as a metamaterial, and can offer unusual macroscopic properties. Here, we take a different approach and limit ourselves to…

Optics · Physics 2019-10-09 S. Metais , G. Lerosey , F. Lemoult

Engineering the directionality and emission rate of quantum light sources is essential in the development of modern quantum applications.In this work we use numerical calculations to optimize the brightness of a broadband quantum emitter…

Optics · Physics 2018-05-01 Hamza Abudayyeh , Ronen Rapaport

Pixel antenna is a promising antenna technology that enables flexible adjustment of radiation characteristics and enhancement of wireless systems through antenna coding. This work proposes a novel deep learning-based antenna coding…

Information Theory · Computer Science 2026-03-02 Binzhou Zuo , Shanpu Shen , Hongyu Li

Ultrafast manipulation of optical resonance can establish the time-boundary effect in time-variant media leading to a new degree of freedom for coherent control of electromagnetic waves. Here, we demonstrate that a free-standing all…

We investigate antenna coding utilizing pixel antennas as a new degree of freedom for enhancing multiple-input multiple-output (MIMO) wireless power transfer (WPT) systems. The objective is to enhance the output direct current (DC) power…

Signal Processing · Electrical Eng. & Systems 2026-01-13 Yijun Chen , Shanpu Shen , Tianrui Qiao , Hongyu Li , Kai-Kit Wong , Ross Murch

We theoretically study the electromagnetic wave radiation of magnons driven by acoustic phonons in systems with strong magnon-phonon interaction. We evaluate the field dependence of radiation intensity spectra which exhibits the avoided…

Mesoscale and Nanoscale Physics · Physics 2022-06-10 Yahui Ji , Chenye Zhang , Tianxiang Nan

Next generation microwave communications systems face several challenges, particularly from congested communications frequencies and complex propagation environments. Taking inspiration from the Yagi-Uda antenna, we present, and…

Antenna technology is at the basis of ubiquitous wireless communication systems and sensors. Radiation is typically sustained by conduction currents flowing around resonant metallic objects that are optimized to enhance efficiency and…

Applied Physics · Physics 2022-03-23 Jason Soric , Younes Ra'di , Diego Farfan , Andrea Alù

All-dielectric resonant nanophotonics is a rapidly developing research field driven by its exceptional application potential for low-loss nanoscale metadevices. The tight confinement of the local electromagnetic fields and interferences in…

Optics · Physics 2018-10-26 Isabelle Staude , Thomas Pertsch , Yuri Kivshar