The Shubnikov Institute of Crystallography, Leninsky prospekt 59, Moscow, 119333 Russia.
Opt Lett. 2011 Jul 15;36(14):2602-4. doi: 10.1364/OL.36.002602.
We discuss the self-imaging effect that occurs in a multimode planar x-ray waveguide (WG) with a nanometer vacuum gap, where an additional longitudinal periodicity has been imposed by a periodical structure (a micron scale step-like grating) on the reflecting sidewalls. Taking into account the general Montgomery conditions and the particular case of Talbot effect, we show that this additional longitudinal periodicity, if suitably designed, can filter out the asymmetric and the high order resonance modes, providing a coherent beam at the exit, even if the WG is illuminated by an incoherent source.
我们讨论了在具有纳米真空间隙的多模平面 X 射线波导（WG）中发生的自成像效应，其中在反射侧壁上施加了周期性结构（微米级阶跃式光栅）以产生附加的纵向周期性。考虑到一般的蒙哥马利条件和泰伯效应的特殊情况，我们表明，如果适当设计，这种附加的纵向周期性可以滤除非对称和高阶共振模式，从而在 WG 由非相干光源照明的情况下，在出口处提供相干光束。
