论文标题
在合成钻石晶体中揭示的小布拉格平面斜率误差
Small Bragg-plane slope errors revealed in synthetic diamond crystals
论文作者
论文摘要
保存波前X射线钻石晶体光学器件对于X射线科学中的众多应用至关重要。带有平坦平面的完美晶体是布拉格衍射中波前保存的先决条件。但是，由于不可避免的晶体缺陷，在实践中很难实现这种情况。在这里，我们使用X射线摇摆曲线成像来研究目前最佳的合成钻石晶体中最小的Bragg-Plane斜率误差，以及它们与完美的硅晶体的比较。我们表明，最佳的钻石晶体中最小的特定斜率错误（自由主义或无应变安装）约为0.15-0.2〜 $ $ $ rad/mm $ $ $^2 $。这些误差仅比我们以完美的硅晶体测量的0.05-0.1〜 $ $ rad/mm $ $ $^2 $ rad/mm $ $^2 $ rad/mm $^2 $ rad/mm $^2 $大的两个因子。在1450 $^{\ circ} $ C的高温退火几乎是完美无瑕的钻石晶体可减少斜率错误，非常接近硅的斜率。需要进一步研究以建立这些晶体的波前保护特性。
Wavefront-preserving x-ray diamond crystal optics are essential for numerous applications in x-ray science. Perfect crystals with flat Bragg planes are a prerequisite for wavefront preservation in Bragg diffraction. However, this condition is difficult to realize in practice because of inevitable crystal imperfections. Here we use x-ray rocking curve imaging to study the smallest achievable Bragg-plane slope errors in the best presently available synthetic diamond crystals and how they compare with those of perfect silicon crystals. We show that the smallest specific slope errors in the best diamond crystals (both freestanding or strain-free mounted) are about 0.15-0.2~$μ$rad/mm$^2$. These errors are only a factor of two larger than the 0.05-0.1~$μ$rad/mm$^2$ specific slope errors we measure in perfect silicon crystals. High-temperature annealing at 1450$^{\circ}$C of almost flawless diamond crystals reduces the slope errors very close to those of silicon. Further investigations are required to establish the wavefront-preservation properties of these crystals.
