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Electroresistance in multipolar antiferroelectric Cu₂Se semiconductor.

ABSTRACT: Electric field-induced changes in the electrical resistance of a material are considered essential and enabling processes for future efficient large-scale computations. However, the underlying physical mechanisms of electroresistance are currently remain largely unknown. Herein, an electrically reversible resistance change has been observed in the thermoelectric α-Cu₂Se. The spontaneous electric dipoles formed by Cu⁺ ions displaced from their positions at the centers of Se-tetrahedrons in the ordered α-Cu₂Se phase are examined, and α-Cu₂Se phase is identified to be a multipolar antiferroelectric semiconductor. When exposed to the applied voltage, a reversible switching of crystalline domains aligned parallel to the polar axis results in an observed reversible resistance change. The study expands on opportunities for semiconductors with localized polar symmetry as the hardware basis for future computational architectures.

SUBMITTER: Bai H

PROVIDER: S-EPMC8664818 | biostudies-literature | 2021 Dec

REPOSITORIES: biostudies-literature

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Electroresistance in multipolar antiferroelectric Cu2Se semiconductor.

Bai Hui H Wu Jinsong J Su Xianli X Peng Haoyang H Li Zhi Z Yang Dongwang D Zhang Qingjie Q Uher Ctirad C Tang Xinfeng X

Nature communications 20211210 1

Electric field-induced changes in the electrical resistance of a material are considered essential and enabling processes for future efficient large-scale computations. However, the underlying physical mechanisms of electroresistance are currently remain largely unknown. Herein, an electrically reversible resistance change has been observed in the thermoelectric α-Cu2Se. The spontaneous electric dipoles formed by Cu+ ions displaced from their positions at the centers of Se- ...[more]

PMID: 34893623

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