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Alternating Current Field Effects in Atomically Ferroelectric Ultrathin Films.

ABSTRACT: In this work, atomically K1-xNaxNbO3 thin films are taken as examples to investigate the reversible and irreversible effects in a horizon plane, i.e., the changes of domain structures, phase states, free energies, etc., under a z-axis alternating current field via a phase-field method. The simulation results show the driving forces during the charging and discharging process, where there is a variation for the angles of the domain walls from 180° to 90° (and then an increase to 135°), which are the external electric field and domain wall evolution, respectively. As for the phase states, there is a transformation between the orthorhombic and rhombohedral phases which can't be explained by the traditional polarization switching theory. This work provides a reasonable understanding of the alternating current field effect, which is essential in information and energy storage.

SUBMITTER: Cao J

PROVIDER: S-EPMC8999760 | biostudies-literature | 2022 Mar

REPOSITORIES: biostudies-literature

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Alternating Current Field Effects in Atomically Ferroelectric Ultrathin Films.

Cao Jinming J Liu Mengxia M Liu Zhonglei Z Hou Hua H Zhao Yuhong Y

Materials (Basel, Switzerland) 20220329 7

In this work, atomically K1-xNaxNbO3 thin films are taken as examples to investigate the reversible and irreversible effects in a horizon plane, i.e., the changes of domain structures, phase states, free energies, etc., under a z-axis alternating current field via a phase-field method. The simulation results show the driving forces during the charging and discharging process, where there is a variation for the angles of the domain walls from 180° to 90° (and then ...[more]

PMID: 35407839

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