Single-cycle surface plasmon polaritons on a bare metal wire excited by relativistic electrons

Abstract

Terahertz (THz) pulses are applied in areas as diverse as materials science, communication and biosensing. Techniques for subwavelength concentration of THz pulses give access to a rapidly growing range of spatial scales and field intensities. Here we experimentally demonstrate a method to generate intense THz pulses on a metal wire, thereby introducing the possibility of wave-guiding and focussing of the full THz pulse energy to subwavelength spotsizes. This enables endoscopic sensing, single-shot subwavelength THz imaging and study of strongly nonlinear THz phenomena. We generate THz surface plasmon polaritons (SPPs) by launching electron bunches onto the tip of a bare metal wire. Bunches with 160 pC charge and ≈6 ps duration yield SPPs with 6–10 ps duration and 0.4±0.1 MV m−1 electric field strength on a 1.5 mm diameter aluminium wire. These are the most intense SPPs reported on a wire. The SPPs are shown to propagate around a 90° bend.

Coherent free-electron light sources

“…Recent experimental studies have studied the generation of a strong THz SPP on a wire waveguide by means of a coherent transition radiation process using a 3 MeV electron impinging on a metal tip [56] as well as the dispersion relation of the THz SPP [57,58] .…”

Towards High-Repetition-Rate Intense Terahertz Source With Metal Wire-Based Plasma

“…waveguide for the THz synchrotron radiation which is collimated and guided immediately by the wire as THz surface plasmon polaritons (SPPs) and then emitted from the end of the wire [26,27]. Consequently, emitted THz synchrotron radiation does not rely on the laser-plasma interaction directly as in the case of foil target.…”

Зависимость Самоиндукции Тонкой Цилиндрической Проволоки Из Металла От Механизма Поверхностного Рассеяния Электронов

“…В последнее время наблюдается растущий интерес к электромагнитным свойствам систем, включающих в себя металлические проволоки малого радиуса [1][2][3][4][5]. Электромагнитные свойства таких систем определяются такими свойствами проволок как электропроводность и индуктивность.…”