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Developments in metamaterials and related structures such as metasurfaces have opened up new possibilities in designing materials and devices with unique properties. The main progress related to electromagnetic waves applications was done…

Medical Physics · Physics 2016-12-13 Rita Schmidt , Alexey Slobozhanyuk , Pavel Belov , Andrew Webb

The performance of radiofrequency (RF) coils has a significant impact on the quality and speed of magnetic resonance imaging (MRI). Consequently, rigid coils with attached cables are commonly employed to achieve optimal SNR performance and…

In this paper we discuss the phenomenon of resonance that we predict will occur when a superconducting coil is submitted simultaneously to a magnetic field and to an external force. When both the force and the magnetic field are constant in…

Superconductivity · Physics 2007-05-23 Osvaldo F. Schilling

Imaging of structural defects in a material can be realized with a radio-frequency atomic magnetometer by monitoring the material's response to a radio-frequency excitation field. We demonstrate two measurement configurations that enable…

Applied Physics · Physics 2019-03-27 P. Bevington , R. Gartman , W. Chalupczak

In this work, we show that propagating waves can be fully converted into surface waves and back using geometrically periodic arrays of simple electrically small metal elements loaded by adjustable reactive loads. The proposed approach…

Optics · Physics 2025-06-19 Yongming Li , Xikui Ma , Viktar Asadchy , Sergei A. Tretyakov

Despite their great potential in communication and sensing applications, printed leaky-wave antennas have rarely been reported at mm-wave frequencies. In this paper, tapered leaky-wave antennas operating at 80 GHz are designed, fabricated…

Applied Physics · Physics 2021-12-07 Andreas E. Olk , Mingkai Liu , David A. Powell

In this paper, a new composite right/left-handed (CRLH) Leaky Wave Antenna (LWA) based on substrate-integrated waveguide (SIW) structures is proposed. The suggested antenna has a continuous beam scanning from backward to forward versus…

Applied Physics · Physics 2023-05-16 Hossein Dolatkhah , Zahra Atlasbaf

Time-harmonic far-field source array imaging in a two-dimensional waveguide is analyzed. A low-frequency situation is considered in which the diameter of the waveguide is slightly larger than the wavelength, so that the waveguide supports a…

Analysis of PDEs · Mathematics 2020-12-02 Josselin Garnier

We will report on the electromagnetic response due to induced dipolar currents in metamaterials of 2-dimensional array of metallic elements. Used as frequency selectors, the metamaterial transmittance presents a single resonance in the…

Optics · Physics 2009-08-04 C. Rizza , E. Palange , P. Carelli , M. Ortolani , O. Limaj , A. Nucara , S. Lupi

Typical acoustic refractive metasurfaces governed by generalized Snell law require several types of subwavelength subunits to provide an extra phase gradient along the surface. This design strategy, however, has several kinds of drawback.…

Applied Physics · Physics 2019-09-18 Zhilin Hou , Xinsheng Fang , Yong Li , Badreddine Assouar

This research focuses on the design and evaluation of an ultrathin cylindrical metasurface for improving the transmit efficiency of traveling-wave magnetic resonance imaging (MRI) of the human brain. To improve efficiency, we matched a…

The purpose of this work is to test the ability of a new class of passive electromagnetic device to increase the penetration depth of phased arrays of surface coils for magnetic resonance (MR) imaging systems. This new device is based on…

Medical Physics · Physics 2009-07-17 Manuel J. Freire , Ricardo Marques , Lukas Jelinek , Eduardo Gil , Francisco Moya

Waveguides have been successfully used to generate magnetic resonance images at 7 T with whole-body systems. The bore limits the magnetic resonance signal transmitted because its specific cut-off frequency is greater than the majority of…

Medical Physics · Physics 2015-06-12 F. Vazquez , R. Martin , O. Marrufo , A. O. Rodriguez

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

Filtering modules are essential devices of modern microwave systems given their capability to improve the signal-to-noise ratio of the received signal or to eliminate the unwanted interferences. For discriminating between different…

In Magnetic Particle Imaging, a field-free region is maneuvered throughout the field of view using a time-varying magnetic field known as the drive-field. Human-sized systems operate the drive-field in the kHz range and generate it by…

Signal Processing · Electrical Eng. & Systems 2024-04-10 Fabian Mohn , Fynn Förger , Florian Thieben , Martin Möddel , Ingo Schmale , Tobias Knopp , Matthias Graeser

The paper proposes the design of a tri-mode coupled coil which enables three modes of operation for inducing electromagnetic field, where the focal adjustment of the E field can be optimized. Methods: The setup consists of two identical…

Medical Physics · Physics 2018-03-28 Raunaq Pradhan , Xiaohua Feng , Zheng Yuanjin

Non-radiative coupling between conductive coils is a candidate mechanism for wireless energy transfer applications. In this paper, we propose a power relay system based on a near-field metamaterial superlens, and present a thorough…

Classical Physics · Physics 2011-07-25 Yaroslav Urzhumov , David R. Smith

The aim of this communication is to investigate and demonstrate the possibility to overcome the fundamental limitations of mantle cloaking for antennas by exploiting nonlinear metasurfaces. First, we recap and give additional physical…

This letter proposes a new method based on ultrafast high energy electron radiography to diagnose transient electromagnetic field. For the traditional methods, large scattering from matter will increase the uncertainty of measurement, but…

Accelerator Physics · Physics 2022-02-09 J. H. Xiao , Y. C. Du , H. Q. Li , Y. T. Zhao , L. Sheng