Ter-Avetisyan S, Schnürer M, Stiel H, Vogt U, Radloff W, Karpov W, Sandner W, Nickles P V
Max-Born-Institut, Max-Born-Strasse 2a, D-12489 Berlin, Germany and Institute for Physical Research, Ashtarak-2, 378410, Armenia.
Phys Rev E Stat Nonlin Soft Matter Phys. 2001 Sep;64(3 Pt 2):036404. doi: 10.1103/PhysRevE.64.036404. Epub 2001 Aug 28.
Large Xe clusters (10(5)-10(6) atoms per cluster) have been irradiated with ultrashort (50 fs) and high-intensity ( approximately 2 x 10(18) W/cm(2)) pulses from a Ti:sapphire multi-TW laser at 800 nm wavelength. Scaling and absolute yield measurements of extreme ultraviolet (EUV) emission in a wavelength range between 7 and 15 nm in combination with cluster target characterization have been used for yield optimization. Maximum emission as a function of the backing pressure and a spatial emission anisotropy covering a factor of two at optimized yields is discussed with a simple model of the source geometry and EUV-radiation absorption. Circularly polarized laser light instead of linear polarization results in a factor of 2.5 higher emission in the 11 to 15 nm wavelength range. This indicates the initial influence of optical-field ionization for the interaction parameter range used and contrasts to collisional heating that seems to influence preferentially higher ionization. Absolute emission efficiency at 13.4 nm of up to 0.5% in 2pi sr and 2.2% bandwidth has been obtained.
已用波长为800nm的钛宝石多太瓦激光器发出的超短（50飞秒）和高强度（约2×10¹⁸W/cm²）脉冲辐照大型氙团簇（每个团簇含10⁵ - 10⁶个原子）。结合团簇靶表征，对7至15nm波长范围内极紫外（EUV）发射进行了标度和绝对产率测量，以优化产率。利用源几何结构和EUV辐射吸收的简单模型，讨论了在优化产率下，作为背压函数的最大发射以及在优化产率下覆盖两倍因子的空间发射各向异性。圆偏振激光而非线偏振激光在11至15nm波长范围内使发射提高2.5倍。这表明在所使用的相互作用参数范围内光场电离的初始影响，并且与似乎优先影响更高电离的碰撞加热形成对比。在2π立体角和2.2%带宽下，已获得13.4nm处高达0.5%的绝对发射效率。
