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A relativistic electron-positron beam propagating through a magnetized electron-ion plasma is shown to generate both circularly and linearly polarized synchrotron radiation. The degrees of circular and linear polarizations depend both on…

Plasma Physics · Physics 2019-05-29 Ujjwal Sinha , Christoph H. Keitel , Naveen Kumar

Ultraviolet pulses could open up new opportunities for the study of strong-field physics and ultrafast science. However, the existing methods for generating ultra-violet pulses face difficulties in fulfilling the twofold requirements of…

Optics · Physics 2024-12-17 Litong Xu , Tingting Xi

Inverse Compton Scattering at shallow angles can be used to tune the spectrum and increase the brightness of the emitted radiation. Here, we report on the demonstration of emission of visible light by a 4.7 MeV $e$-beam crossing a 780 nm…

Accelerator Physics · Physics 2025-09-08 B. H. Schaap , M. Lenz , P. Musumeci

High-energy vortex $\gamma$ photons have significant applications in many fields, however, their generation and angular momentum manipulation are still great challenges. Here, we first investigated the generation of vortex $\gamma$ photons…

High Energy Physics - Phenomenology · Physics 2025-03-18 Jing-Jing Jiang , Kai-Hong Zhuang , Jia-Ding Chen , Jian-Xing Li , Yue-Yue Chen

An optical frequency comb generated with an electro-optic phase modulator and a chirped radiofrequency waveform is used to perform saturation and pump-probe spectroscopy on the $D_1$ and $D_2$ transitions of atomic potassium. With a comb…

Atomic Physics · Physics 2016-12-21 David A. Long , Adam J. Fleisher , David F. Plusquellic , Joseph T. Hodges

We demonstrate a frequency-stabilized, all-solid laser source at 589 nm with up to 800 mW output power. The laser relies on sum-frequency generation from two laser sources at 1064 nm and 1319 nm through a PPKTP crystal in a doubly-resonant…

We discuss radiation generated by positrons channeling in a crystalline undulator. The undulator is produced by periodically bending a single crystal with an amplitude much larger than the interplanar spacing. Different approaches for…

Accelerator Physics · Physics 2017-08-23 A. V. Korol , W. Krause , A. V. Solov'yov , W. Greiner

Controlling the spectral and angular response of infrared (IR) radiation is a challenging task of paramount importance to various emerging photonic applications. Here, we overcome these problems by proposing and analyzing a new design of a…

Optics · Physics 2022-10-13 Andrew Butler , Jack Schulz , Christos Argyropoulos

We put forward a novel method to generate high-brilliance polarized $\gamma$-photon beams via vacuum dichroism (VD)-assisted vacuum birefringence (VB) effect. We split a linearly polarized (LP) laser pulse into two subpulses with the first…

Plasma Physics · Physics 2024-05-01 Chong Lv , Feng Wan , Yousef I. Salamin , Qian Zhao , Mamutjan Ababekri , Ruirui Xu , Jian-Xing Li

Here we present the study of a compact emission source during an X1.3 flare on 2022-March-30. Within a $\sim41$~s period (17:34:48 UT to 17:35:29 UT), IRIS observations show spectral lines of Mg II, C II and Si IV with extremely broadened,…

Solar and Stellar Astrophysics · Physics 2023-09-13 Yan Xu , Graham S. Kerr , Vanessa Polito , Nengyi Huang , Ju Jing , Haimin Wang

We compute the interaction of a sodium vapor with a static magnetic field ranging from 0 up to 1 Tesla, which allows to obtain the behavior of all Zeeman transitions as a function of the magnetic field for any polarization of incident laser…

Atomic Physics · Physics 2021-07-14 Rodolphe Momier , Aram V. Papoyan , Claude Leroy

We show that planar a plasmonic metamaterial with spatially variable meta-atom parameters can focus transmitted light into sub-wavelength hot-spots located beyond the near-field of the metamaterial. By nano-structuring a gold film we…

Optics · Physics 2015-06-12 Tapashree Roy , Edward T. F. Rogers , Nikolay I. Zheludev

The generation of relativistic vortex electron beams via photoemission requires ultraviolet laser beams with well-controlled orbital angular momentum (OAM) and compatibility with radio-frequency (RF) photoinjector drive-laser systems.…

The generation of very narrow linewidth light sources is of great importance in modern science. One such source is the superradiant laser, which relies on collectively interacting ultra long lived dipoles driven by incoherent light. Here we…

Quantum Physics · Physics 2023-02-23 Diego Barberena , Robert J. Lewis-Swan , Ana Maria Rey , James K. Thompson

High harmonic generation traditionally combines ~100 near-infrared laser photons, to generate bright, phase matched, extreme ultraviolet beams when the emission from many atoms adds constructively. Here we show that by guiding a…

By coupling silicon nanowires (~150 nm diameter, 20 micron length) with an {\Omega}-shaped plasmonic nanocavity we are able to generate broadband visible luminescence, which is induced by high-order hybrid nanocavity-surface plasmon modes.…

Materials Science · Physics 2015-06-18 Carlos O. Aspetti , Chang-Hee Cho , Rahul Agarwal , Ritesh Agarwal

Narrow bandwidth, high energy photon sources can be generated by Thomson scattering of laser light from energetic electrons, and detailed control of the interaction is needed to produce high quality sources. We present analytic calculations…

Plasma Physics · Physics 2014-12-09 S. G. Rykovanov , C. G. R. Geddes , J. -L. Vay , C. B. Schroeder , E. Esarey , W. P. Leemans

We describe a tunable broadband mid-infrared laser source based on difference-frequency mixing of a 100 MHz femtosecond Yb:fiber laser oscillator and a Raman-shifted soliton generated with the same laser. The resulting light is tunable over…

Optics · Physics 2015-05-30 Tyler W. Neely , Todd A. Johnson , Scott A. Diddams

We consider atomic strong-field ionization in the long-pulse limit for linearly polarized infrared laser fields. We show how nondipole effects in the plane formed by the propagation and polarization directions lead to (i) a shift of the…

Atomic Physics · Physics 2021-11-10 Mads Middelhede Lund , Lars Bojer Madsen

We optically excite $^{85}$Rb atoms in a heated vapor cell to a low-lying Rydberg state 10D$_{5/2}$ and observe directional terahertz (THz) beams at 3.3 THz and 7.8 THz. These THz fields are generated by amplified spontaneous emission from…

Atomic Physics · Physics 2021-03-10 Mark Lam , Sambit B. Pal , Thibault Vogt , Martin Kiffner , Wenhui Li