Snigirev A, Bjeoumikhov A, Erko A, Snigireva I, Grigoriev M, Yunkin V, Erko M, Bjeoumikhova S
European Synchrotron Radiation Facility, 6 rue Jules Horowitz, 38043 Grenoble, France.
J Synchrotron Radiat. 2007 Jul;14(Pt 4):326-30. doi: 10.1107/S0909049507025174. Epub 2007 Jun 14.
A two-step focusing set-up combining a Fresnel zone plate with an ellipsoidal capillary is presented. It is shown that, in addition to the anticipated gain in flux, the employment of the prefocusing micro-optic makes optimal use of the elliptical shape of the capillary by almost eliminating aberrations. A small cross section of the prefocused beam allows a tiny fraction of the capillary surface to be selected, thus reducing the influence of slope errors. An X-ray beam with a 15 keV energy was focused down to a spot size as small as 250 nm, demonstrating the best value that has been achieved up to now for single-bounce capillaries. The use of an ellipsoidal capillary as a micromirror under off-axis illumination by microfocusing optics may open up new opportunities in nanofocusing developments.
本文介绍了一种将菲涅耳波带片与椭圆形毛细管相结合的两步聚焦装置。结果表明，除了预期的通量增益外，预聚焦微光学器件的使用通过几乎消除像差，使毛细管的椭圆形得到了最佳利用。预聚焦光束的小横截面允许选择毛细管表面的一小部分，从而减少斜率误差的影响。一个能量为15 keV的X射线束被聚焦到小至250 nm的光斑尺寸，这展示了目前单反射毛细管所达到的最佳值。在微聚焦光学器件的离轴照明下，将椭圆形毛细管用作微镜可能会为纳米聚焦发展带来新的机遇。
