Far-infrared Spectra of the Alloy of Germanium-Antimony-tellurium in the Glassy and Crystalline State
V. A. Ryzhov *
Ioffe Physical-Technical Institute, Russian Academy of Science, 194021 St-Petersburg, Russia
D. Arsova
Institute of Solid State Physics, Bulgarian Academy of Science, 1784 Sofia, Bulgaria
*Author to whom correspondence should be addressed.
Abstract
Far-infrared spectra of a germanium-antimony-tellurium alloy in the glassy and crystalline states have been measured and analyzed in the frequency range 20–400 cm-1 at room temperature. The absorption in this range is due to the phonon modes of the structural units of crystalline and correlated librational vibrations (boson peak) of glassy alloy, which precede the appearance of relaxation dynamics. The vibrational assignments of various absorption bands and the differences revealed in the spectra will make it possible to more confidently elucidate the possible molecular mechanism of the crystal-to-amorphous transition in other chalcogenide alloys. New details of the crystal-to-amorphous transition scenario are suggested.
Keywords: Far-infrared spectra, phonons, boson peak, chalcogenide, phase transition