Pulse-to-Pulse Stable Bright Laser-Sustained Plasma Source by Time-Domain Modulation

Release time:2025-07-04 Hits:

DOI number:10.1002/lpor.202500877

Journal:Laser Photonics Rev.

Key Words:broadband source, laser-sustained plasma, time-domain modulation

Abstract:Laser-sustained plasma (LSP) source characterized by superior brightness, ultraviolet extension, and broadband spectral coverage has been utilized as an essential component in advanced imaging and inspection equipment extensively. Brightness is the primary factor determining the bottleneck of inspection speed at the application ends. However, the fundamental“upstream” effect produces the contradiction between laser power and brightness. Plasma grows against the direction of laser incidence due to the inhomogeneous spatial distribution of plasma absorption coefficient and laser power density. In this paper, a plasma source sustained by laser with periodic shutdown is proposed, hence breaking through the brightness limitation. Quantitative analysis of the spatiotemporal distribution of plasma temperature during the periodic evolution is presented specifically based on the constructed 2D transient fluid model. A conceptual progress that the time-domain modulation of the laser conspicuously elevates plasma temperature by suppressing the “upstream” effect is reported. Experimental results demonstrate that modulated LSP enhances the plasma emission intensity with merely half of the laser power consumption. By establishing the quantitative link between laser time-domain characteristics and plasma spatiotemporal evolution, this work presents a pulse-to-pulse stable bright LSP source, which is essential to high-speed inspection and spectroscopy applications.

Co-author:He Hu,Zhaojiang Shi

First Author:Shichao Yang

Indexed by:Article

Correspondence Author:Xia Yu

Translation or Not:no

Date of Publication:2025-06-07

Included Journals:SCI