Terahertz annular antenna driven with a short intense laser pulse

TL;DR

This paper investigates a novel annular antenna design with a slit that, when irradiated by a short intense laser pulse, efficiently generates and controls terahertz radiation through plasma-mediated discharge oscillations.

Contribution

It introduces a new geometry of an annular target with a slit as an effective terahertz emitter driven by laser pulses, enabling controlled discharge oscillations.

Findings

Efficient terahertz generation along the coil axis.

The slit acts as a diode controlling discharge propagation.

Multiple passes of discharge enhance terahertz emission.

Abstract

Generation of terahertz radiation by an oscillating discharge, excited with short laser pulses, may be controlled by geometry of the irradiated target. In this work, an annular target with a thin slit is considered as an efficient emitter of secondary radiation when driven by a short intense laser pulse. Under the irradiation, a slit works as a diode, which is quickly filled by dense plasma, closing the circuit for a travelling discharge pulse. Such a diode defines the discharge pulse propagation direction in a closed contour, enabling its multiple passes along the coil.The obtained oscillating charge efficiently generates terahertz waves with a maximum along the coil axis and controllable characteristics.