Study at FLASH: XUV lasing from exploding noble-gas nanoclusters

New mechanism of XUV light amplification

An international team of scientists, headed by Nina Rohringer from DESY and Unversität Hamburg, has succeeded in getting bursts of laser-like extreme ultraviolet (XUV) emission from noble-gas clusters in the transient warm dense matter state. Xenon clusters were irradiated by DESY’s free-electron laser FLASH, and the resulting strongly amplified fluorescence signal was analysed by a high-resolution spectrometer. Theoretical modeling of the process indicates that the clusters, transformed to a nanometer-sized plasma (‘nanoplasma’), enable the creation of population inversion by means of electron-ion collisions. The transient but sizeable population inversion of the ensemble of clusters enables amplification of spontaneous emission in a single pass of the emitted XUV radiation. This study, performed at the CAMP station of the FLASH beamline BL1 at DESY, is published in Physical Review A and is highlighted as an Editors’ Suggestion.

>Read more on the FLASH website

Image: Excited noble-gas clusters stimulate lasting emission in the forward direction. (Credit: Original publication in Phys. Reb. A (2020))