强自由电子激光脉冲对氖和氩的少光子多电离

Few-photon multiple ionization of ne and ar by strong free-electron-laser pulses.

作者信息

Moshammer R, Jiang Y H, Foucar L, Rudenko A, Ergler Th, Schröter C D, Lüdemann S, Zrost K, Fischer D, Titze J, Jahnke T, Schöffler M, Weber T, Dörner R, Zouros T J M, Dorn A, Ferger T, Kühnel K U, Düsterer S, Treusch R, Radcliffe P, Plönjes E, Ullrich J

机构信息

Max-Planck-Institut für Kernphysik, Saupfercheckweg 1, 69117 Heidelberg, Germany.

出版信息

Phys Rev Lett. 2007 May 18;98(20):203001. doi: 10.1103/PhysRevLett.98.203001. Epub 2007 May 14.

DOI:10.1103/PhysRevLett.98.203001

PMID:17677687

Abstract

Few-photon multiple ionization of Ne and Ar atoms by strong vacuum ultraviolet laser pulses from the free-electron laser at Hamburg was investigated differentially with the Heidelberg reaction microscope. The light-intensity dependence of Ne2+ production reveals the dominance of nonsequential two-photon double ionization at intensities of I<6x10(12) W/cm2 and significant contributions of three-photon ionization as I increases. Ne2+ recoil-ion-momentum distributions suggest that two electrons absorbing "instantaneously" two photons are ejected most likely into opposite hemispheres with similar energies.

摘要

利用海德堡反应显微镜对来自汉堡自由电子激光的强真空紫外激光脉冲引发的氖和氩原子的少光子多电离进行了差分研究。氖离子（Ne2+）产生的光强依赖性表明，在强度I<6×10¹² W/cm²时，非顺序双光子双电离占主导，随着I增加，三光子电离的贡献显著。Ne2+反冲离子动量分布表明，两个“瞬间”吸收两个光子的电子最有可能以相似能量被喷射到相反半球。