Phys. Rev. Lett. 104, 105702 (2010) [4 pages]Origin of Pressure-Induced Polyamorphism in Ce75Al25 Metallic GlassReceived 29 December 2009; revised 29 January 2010; published 11 March 2010 Using high-pressure synchrotron x-ray absorption spectroscopy, we observed the Ce 4f electron in Ce75Al25 metallic glass transform from its ambient localized state to an itinerant state above 5 GPa. A parallel x-ray diffraction study revealed a volume collapse of about 8.6%, coinciding with 4f delocalization. The transition started from a low-density state below 1.5 GPa, went through continuous densification ending with a high-density state above 5 GPa. This new type of electronic polyamorphism in densely packed metallic glass is dictated by the Ce constituent, and is fundamentally distinct from the well-established structural polyamorphism in which densification is caused by coordination change and atomic rearrangement. © 2010 The American Physical Society URL:
http://link.aps.org/doi/10.1103/PhysRevLett.104.105702
DOI:
10.1103/PhysRevLett.104.105702
PACS:
64.70.kj, 61.50.Ks, 71.23.Cq, 81.30.Hd
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