Abstract
Crystal structures of optical recording materials Ge2Sb2+xTe5 and GeBi2Te4 have been studied in terms of the fast phase transition mechanism by both real- and reciprocal-space Rietveld analyses of pulsed neutron powder diffraction data. These crystalline phases had large local lattice distortions. In addition, the crystallite size of GeBi2Te4 was very small (about 150 Å). These results suggest that the similarity of entropy between crystalline and amorphous phases plays an important role in terms of the fast phase transition mechanism.
Original language | English |
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Pages (from-to) | 574-577 |
Number of pages | 4 |
Journal | Physica B: Physics of Condensed Matter |
Volume | 385-386 I |
DOIs | |
State | Published - Nov 27 2006 |
Externally published | Yes |
Funding
The authors thank Mr. K. Kawahara for sample preparation. This work was supported by a Grant-in-Aid for Scientific Research from the Ministry of Education, Culture, Sports, Science and Technology of Japan. Los Alamos National Laboratory is funded by DOE under Contract no. W-7405-ENG-36. The upgrade of NPDF has been funded by NSF through Grant no. DMR 00-76488.
Keywords
- DVD
- Fast phase transition mechanism
- Neutron powder diffraction
- Optical recording material
- PDF analysis