The temporal local structure evolution of amorphous state to amorphous state under high pressure is a virgin field that has not been extensively explored. With instrumental developments in the collection of sparse scattering signals and to an increased flux and coherence of X-ray beams, X-ray photon correlation spectroscopy (XPCS) has recently emerged as a very powerful technique able to follow the evolution of the dynamics at the atomic length scale in crystalline and amorphous materials [1-3]. Different from the conventional diffraction and scattering methods, which offer the information of average structures over the diffraction volume in sample, the XPCS could uncover the local order from time domain when the coherent beam size is equal to the illuminated sample volume, and exposure time is shorter than the onset time for the speckle dynamics. So the temporal relaxation procedure on the origin of amorphous state to another amorphous state transition process upon compression could be monitored. XPCS experiments under high pressure conditions were performed at room temperature by a collaborative team from Harbin Institute of Technology, HPSTAR, beamline scientists from 8-ID of APS and 11-ID of NSLS-2 in last couple of years. In this paper, we will present recently results on selected typical metallic glass systems, such as Ti-Cu glass which remain stable up to 30 GPa [4], and Ce-Al system with 4f electronic driving transition happen at about 3 GPa [5], which demonstrates the correlation change during transformation.

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[4]. Liangliang Li, Luhong Wang, Renfeng Li, et al., Constant real-space fractal dimensionality and structure evolution in Ti₆₂Cu₃₈ metallic glass under high pressure, Physical Review B, 94, 184201, 2016.

[5]. Hongwei Sheng, Haozhe Liu, Yongqiang Cheng, et al., Polyamorphism in a metallic glass, Nature Materials, 6, 3, 192, 2007.