title: Suppression of Bragg reflection glitches of a single-crystal diamond anvil cell by a polycapillary half-lens in high-pressure XAFS spectroscopy.
abstract: In combination with a single-crystal diamond anvil cell (DAC), a polycapillary half-lens (PHL) re-focusing optics has been used to perform high-pressure extended X-ray absorption fine-structure measurements. It is found that a large divergent X-ray beam induced by the PHL leads the Bragg glitches from single-crystal diamond to be broadened significantly and the intensity of the glitches to be reduced strongly so that most of the DAC glitches are efficiently suppressed. The remaining glitches can be easily removed by rotating the DAC by a few degrees with respect to the X-ray beam. Accurate X-ray absorption fine-structure (XAFS) spectra of polycrystalline Ge powder with a glitch-free energy range from -200 to 800 eV relative to the Ge absorption edge are obtained using this method at high pressures up to 23.7 GPa, demonstrating the capability of PHL optics in eliminating the DAC glitches for high-pressure XAFS experiments. This approach brings new possibilities to perform XAFS measurements using a DAC up to ultrahigh pressures.
authors: Beijing Synchrotron Radiation Facility, Institute of High Energy Physics, Chinese Academy of Sciences, Beijing, People's Republic of China.
authors: Dongliang
authors: D
authors: Chen
authors: Juncai
authors: J
authors: Dong
authors: Xiaoli
authors: X
authors: Zhang
authors: Peiyu
authors: P
authors: Quan
authors: Yaxiang
authors: Y
authors: Liang
authors: Tiandou
authors: T
authors: Hu
authors: Jing
authors: J
authors: Liu
authors: Xiang
authors: X
authors: Wu
authors: Qian
authors: Q
authors: Zhang
authors: Yude
authors: Y
authors: Li
keywords: DAC; Ge K-edge; high-pressure µ-XAFS; polycapillary half-lens optics