Anomalous compression behavior in lanthanum/cerium-based metallic glass under high pressure

*International Center for New-Structured Materials (ICNSM) and Laboratory of New-Structured Materials, Department of Materials Science and Engineering, and
^‡Analysis and Testing Centre, Zhejiang University, Hangzhou 310027, People's Republic of China;
^†Institute of High Energy Physics, Chinese Academy of Sciences, Beijing 10039, People's Republic of China;
^§High Pressure Collaborative Access Team and
**Experimental Facility Division, Advanced Photon Source, Argonne National Laboratory, Argonne, IL 60439; and
^¶Geophysical Laboratory, Carnegie Institution of Washington, Washington, DC 20015

Contributed by H.-k. Mao, June 28, 2007 (received for review May 20, 2007)

Abstract

In situ high-pressure x-ray diffraction, low-temperature resistivity, and magnetization experiments were performed on a La₃₂Ce₃₂Al₁₆Ni₅Cu₁₅ bulk metallic glass (BMG). A sudden change in compressibility at ≈14 GPa and a rapid increase of resistivity at ≈12 K were detected, whereas magnetic phase transformation and magnetic field dependence of the low-temperature resistivity do not occur at temperatures down to 4.2 K. An interaction between conduction electrons and the two-level systems is suggested to explain the temperature and field dependences of resistivity of the BMG alloy. Although the cause of the unusual change in compressibility at ≈14 GPa is not clear, we believe that it could be linked with the unique electron structure of cerium in the amorphous matrix. An electronic phase transition in BMG alloys, most likely a second-order amorphous-to-amorphous phase transition, is suggested.

Footnotes

^‖To whom correspondence may be addressed. E-mail: jiangjz{at}zju.edu.cn or h.mao{at}gl.ciw.edu
Author contributions: J.Z.J. designed research; Q.S.Z., Y.C.L., C.M.F., P.L., M.S., G.Y.S., H.-k.M., R.Y., J.L., T.D.H., and J.Z.J. performed research; J.Z.J. contributed new reagents/analytic tools; Q.S.Z., H.-k.M., and J.Z.J. analyzed data; and J.Z.J. wrote the paper.
The authors declare no conflict of interest.
Abbreviation:

BMG,

bulk metallic glass.