LOCAL STRUCTURE OF Ge-Sb-Te AND ITS MODIFICATION UPON THE PHASE TRANSITION
نویسندگان
چکیده
Center for Applied Near-Field Optics Research, National Institute of Advanced Industrial Science and Technology, Tsukuba Central 4, 1-1-1 Higashi, Tsukuba, Ibaraki 305-8562, Japan Department of Physics, Yeshiva University, 245 Lexington Avenue, New York, NY 10016, USA Department of Physics, Box 351560, University of Washington, Seattle, WA 98195, USA SPring-8, Japan Synchrotron Radiation Research Institute, Mikazuki, Hyogo 679-5198, Japan
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Observation of T2-like coherent optical phonons in epitaxial Ge2Sb2Te5/GaSb(001) films
The phonon spectrum of Ge₂Sb₂Te₅ is a signature of its crystallographic structure and underlies the phase transition process used in memory applications. Epitaxial materials allow coherent optical phonons to be studied in femtosecond anisotropic reflectance measurements. A dominant phonon mode with frequency of 3.4 THz has been observed in epitaxial Ge₂Sb₂Te₅ grown on GaSb(001). The dependence ...
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