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Related papers: Permanent Magnets Undulator for Terahertz FEL

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Permanent magnet electron optics offer many advantages over electromagnets, and are being increasingly used in high-energy (GeV) electron accelerator designs. Here, we identify the advantages of permanent magnet electron optics for…

Accelerator Physics · Physics 2026-05-29 Ameya Patwardhan , Bas van der Geer , Jom Luiten , Julius Huijts

The magnetic circular dichroism and the Faraday rotation are the fundamental phenomena of great practical importance arising from the breaking of the time reversal symmetry by a magnetic field. In most materials the strength and the sign of…

A THz laser generation utilizing a helical relativistic electron beam propagating through a strong magnetic field is discussed. The initial amplification rate in this scheme is much stronger than that in the conventional free electron…

Optics · Physics 2011-11-08 S. Son , S. J. Moon

Electrons in a periodic lattice can propagate without scattering for macroscopic distances despite the presence of the non-uniform Coulomb potential due to the nuclei. Such ballistic motion of electrons allows the use of a transverse…

Mesoscale and Nanoscale Physics · Physics 2015-06-12 Thiti Taychatanapat , Kenji Watanabe , Takashi Taniguchi , Pablo Jarillo-Herrero

Terahertz spin waves could be generated on-demand via all-optical manipulation of magnetization by femtosecond laser pulse. Here, we present an energy balance model, which explains the energy transfer rates from laser pulse to electron bath…

Materials Science · Physics 2020-05-08 Saeedeh Mokarian Zanjani , Mehmet C. Onbaşlı

We address two finite size effects in perpendicular transport through magnetic multilayers. When the magnetic layer thickness in spin valves becomes of the order or smaller than the spin-flip diffusion length, structural asymmetries affect…

Mesoscale and Nanoscale Physics · Physics 2015-06-25 Alexey A. Kovalev , Gerrit E. W. Bauer , Arne Brataas

Inertial magnetization dynamics have been predicted at ultrahigh speeds, or frequencies approaching the energy relaxation scale of electrons, in ferromagnetic metals. Here we identify inertial terms to magnetization dynamics in thin…

Materials Science · Physics 2016-01-26 Yi Li , Anne-Laure Barra , Stephane Auffret , Ursula Ebels , William E. Bailey

We compute mean waiting times between thermally-activated magnetization reversals in a nanodisk with parameters similar to a free CoFeB layer used in magnetic random access memories. By combining Langer's theory and forward flux sampling…

Mesoscale and Nanoscale Physics · Physics 2020-09-09 L. Desplat , J. -V. Kim

The magnetic properties of thin-film Pd/Fe/Pd trilayers in which an embedded ~1.5 A-thick ultrathin layer of Fe induces ferromagnetism in the surrounding Pd have been investigated. The thickness of the ferromagnetic trilayer is controlled…

Mesoscale and Nanoscale Physics · Physics 2015-05-18 R. K. Das , R. Misra , S. Tongay , R. Rairigh , A. F. Hebard

Magnetization reversal in permanent magnets occurs by the nucleation and expansion of reversed domains. Micromagnetic theory offers the possibility to localize the spots within the complex structure of the magnet where magnetization…

Materials Science · Physics 2018-05-25 J. Fischbacher , A. Kovacs , L. Exl J. Kühnel , E. Mehofer , H. Sepehri-Amin , T. Ohkubo , K. Hono , T. Schrefl

In this paper, a fully coherent radiation option with controllable polarization is proposed for Shanghai deep ultraviolet free electron laser (FEL) test facility. Intensive start-to-end simulation suggests that, the two crossed planar…

Using the $\alpha$-T$_3$ model, we carried out analytical and numerical calculations for the static and dynamic polarization functions in the presence of a perpendicular magnetic field. These results were employed to determine the…

Mesoscale and Nanoscale Physics · Physics 2021-02-17 Antonios Balassis , Dipendra Dahal , Godfrey Gumbs , Andrii Iurov , Danhong Huang , Oleksiy Roslyak

Magnetic-edge magnetoplasmons (MEMPs) are obtained for a two-dimensional electron system (2DES) with atop semi-infinite metallic gate, at a distance $d$, and atop semi-infinite ferromagnetic film at a strong perpendicular magnetic field.…

Mesoscale and Nanoscale Physics · Physics 2016-08-05 Oleg G. Balev , Ivan A. Larkin

The dynamics of magnetic moments consist of a precession around the magnetic field direction and a relaxation towards the field to minimize the energy. While the magnetic moment and the angular momentum are conventionally assumed to be…

Other Condensed Matter · Physics 2023-06-14 Ritwik Mondal , Levente Rózsa , Michael Farle , Peter M. Oppeneer , Ulrich Nowak , Mikhail Cherkasskii

We present the design, fabrication, and characterization of a metamaterial absorber which is resonant at terahertz frequencies. We experimentally demonstrate an absorptivity of 0.97 at 1.6 terahertz. Importantly, this free-standing absorber…

This is a brief overview of the main physical ideas for application of field effect transistors for generation and detection of TeraHertz radiation. Resonant frequencies of the two-dimensional plasma oscillations in FETs increase with the…

Other Condensed Matter · Physics 2015-05-27 M. I. Dyakonov

This paper describes results of magnetic field measurements of white dwarfs carried out on the 6-m telescope for the last years. A magnetic field of about Be ~ 28 kG has been discovered in the degenerate star WD 1953-011. A rotational…

Astrophysics · Physics 2007-05-23 S. N. Fabrika , G. G. Valyavin , T. E. Burlakova , E. A. Barsukova , D. N. Monin

We consider the time evolution of entanglement in a finite two dimensional transverse Ising model. The model consists of a set of 7 localized spin-1/2 particles in a two dimensional triangular lattice coupled through nearest neighbor…

Quantum Physics · Physics 2015-03-18 Qing Xu , Gehad Sadiek , Sabre Kais

Two high field quality quadrupole magnets QF1FF and QD0FF are required for the final focus system of the ATF3. In this paper we focus on the design of the QF1FF magnet. The proposed design is a permanent magnet quadrupole (PMQ) with…

Accelerator Physics · Physics 2012-02-29 Alexey Vorozhtsov , Michele Modena

A common scientific inverse problem is the placement of magnets that produce a desired magnetic field inside a prescribed volume. This is a key component of stellarator design, and recently permanent magnets have been proposed as a…

Plasma Physics · Physics 2022-10-05 Alan A. Kaptanoglu , Tony Qian , Florian Wechsung , Matt Landreman