Nonvolatile Isomorphic Valence Transition in SmTe Films.

ABSTRACT: The burgeoning field of optoelectronic devices necessitates a mechanism that gives rise to a large contrast in the electrical and optical properties. A SmTe film with a NaCl-type structure demonstrates significant differences in resistivity (over 10⁵) and band gap (approximately 1.45 eV) between as-deposited and annealed films, even in the absence of a structural transition. The change in the electronic structure and accompanying physical properties is attributed to a rigid-band shift triggered by a valence transition (VT) between Sm²⁺ and Sm³⁺. The stress field within the SmTe film appears closely tied to the mixed valence state of Sm, suggesting that stress is a driving force in this VT. By mixing the valence states, the formation energy of the low-resist

SUBMITTER: Hatayama S 

PROVIDER: S-EPMC10832057 | biostudies-literature | 2024 Jan

REPOSITORIES: biostudies-literature