Continuous point-like high-temperature laser discharge produced by terahertz free electron laser

Abstract

A continuous point-like laser discharge of record high temperature has been produced in argon at atmospheric pressure with focusing of the radiation of the Novosibirsk terahertz free electron laser (NovoFEL). According to spectral measurements, the temperature in the center of the millimeter-sized plasma sphere was 28000 K at a plasma density of 1.5×1017 cm-3 and an average NovoFEL power of 200 W at a wavelength of 130 μm (2.3 THz).