| Autor: |
Bokova M; Laboratoire de Physico-Chimie de l'Atmosphère, Université du Littoral Côte d'Opale, 59140 Dunkerque, France., Tverjanovich A; Institute of Chemistry, St. Petersburg State University, 198504 St. Petersburg, Russia., Benmore CJ; X-ray Science Division, Advanced Photon Source, Argonne National Laboratory, Argonne, Illinois 60439, United States., Fontanari D; Laboratoire de Physico-Chimie de l'Atmosphère, Université du Littoral Côte d'Opale, 59140 Dunkerque, France., Sokolov A; Laboratoire de Physico-Chimie de l'Atmosphère, Université du Littoral Côte d'Opale, 59140 Dunkerque, France.; ILIT RAS-Branch of the FSRC 'Crystallography and Photonics' RAS, 140700 Shatura, Moscow Region, Russia., Khomenko M; ILIT RAS-Branch of the FSRC 'Crystallography and Photonics' RAS, 140700 Shatura, Moscow Region, Russia., Kassem M; Laboratoire de Physico-Chimie de l'Atmosphère, Université du Littoral Côte d'Opale, 59140 Dunkerque, France., Ozheredov I; ILIT RAS-Branch of the FSRC 'Crystallography and Photonics' RAS, 140700 Shatura, Moscow Region, Russia., Bychkov E; Laboratoire de Physico-Chimie de l'Atmosphère, Université du Littoral Côte d'Opale, 59140 Dunkerque, France.; ILIT RAS-Branch of the FSRC 'Crystallography and Photonics' RAS, 140700 Shatura, Moscow Region, Russia. |
| Abstrakt: |
Binary Ge-Te and ternary Ge-Sb-Te systems belong to flagship phase-change materials (PCMs) and are used in nonvolatile memory applications and neuromorphic computing. The working temperatures of these PCMs are limited by low- T glass transition and crystallization phenomena. Promising high- T PCMs may include gallium tellurides; however, the atomic structure and transformation processes for amorphous Ga-Te binaries are simply missing. Using high-energy X-ray diffraction and Raman spectroscopy supported by first-principles simulations, we elucidate the short- and intermediate-range order in bulk glassy Ga x Te 1- x , 0.17 ≤ x ≤ 0.25, following their thermal, electric, and optical properties, revealing a semiconductor-metal transition above melting. We also show that a phase change in binary Ga-Te is characterized by a very unusual nanotectonic compression with the high internal transition pressure reaching 4-8 GPa, which appears to be beneficial for PCM applications increasing optical and electrical contrast between the SET and RESET states and decreasing power consumption. |
