摘要
High harmonic generation in gas jets was investigated in different gases up to more than 14 bar backing pressure. The observation of increase of harmonic intensity with increasing pressure and laser intensity shows evidence of the presence of clusters in Xe with an increased efficiency compared with He, whereas Ar is an intermediate case for which clusters will start to dominate above a certain backing pressure. Spectral investigations give evidence for tunable harmonic generation in a broad spectral range. A spectral shift of opposite signature caused by the free electrons in the focal volume and the nanoplasmas inside the cluster was observed.
High harmonic generation in gas jets was investigated in different gases up to more than 14 bar backing pressure. The observation of increase of harmonic intensity with increasing pressure and laser intensity shows evidence of the presence of clusters in Xe with an increased efficiency compared with He, whereas Ar is an intermediate case for which clusters will start to dominate above a certain backing pressure. Spectral investigations give evidence for tunable harmonic generation in a broad spectral range. A spectral shift of opposite signature caused by the free electrons in the focal volume and the nanoplasmas inside the cluster was observed.
基金
supported by the European Communities under the contract of the Association between EURATOM and the Hungarian Academy of Sciences, was carried out within the framework of the European Fusion Development Agreement
supported by the Hungarian contract No. ELI 091-2010-0010 hELIos-ELI, project 109257 of the Hungarian Scientific Research Fund and the COST MP1208 and MP1203 activities
supported by a postdoctoral fellowship of the Hungarian Academy of Sciences
