ABSTRACT Both micro-paired and conical support type double-stage diamond anvil cells (ds-DAC) were tested using a newly synthesized ultra-fine nano-polycrystalline diamond (NPD). Well-focused X-ray sub-micron beam and the conically supported 2nd stage anvils (micro-anvils) with 10 μm culet enable us to obtain good quality X-ray diffraction peaks from the sample at around 400 GPa. The relationship between confining pressure and sample pressure depends heavily on the initial height (thickness) of micro-anvils, the difference of a few micrometers leads to a quite different compression path. The conical support type is a solution to retain both enough thickness and strength of micro-anvils at higher confining pressure conditions. All conical support ds-DAC experiments terminated by the failure of the 1st stage anvil instead of 2nd one. The combination of ultra-fine NPD 2nd stage anvil and NPD 1st stage anvil opens a new frontier for measurement of the X-ray absorption spectrum above 300 GPa.

中文翻译：

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双级金刚石砧座用锥形支架

摘要 使用新合成的超细纳米多晶金刚石 (NPD) 对微配对和锥形支撑型双级金刚石砧座 (ds-DAC) 进行了测试。聚焦良好的 X 射线亚微米光束和带有 10 μm 尖底的锥形支撑的第二级砧（微砧）使我们能够在 400 GPa 左右从样品中获得高质量的 X 射线衍射峰。围压与样品压力之间的关系很大程度上取决于微砧的初始高度（厚度），几微米的差异导致压缩路径大不相同。锥形支撑类型是一种在较高围压条件下保持微砧足够厚度和强度的解决方案。所有锥形支撑 ds-DAC 实验都因第一阶段砧座而不是第二阶段的失败而终止。