Atomic-scale mechanism of internal structural relaxation screening at polar interfaces

Li, Mingqiang1,2,3; Cheng, Xiaoxing4; Li, Ning1,2,3; Liu, Heng-Jui5; Huang, Yen-Lin6; Liu, Kaihui3,7,8; Chu, Ying-Hao6,9; Yu, Dapeng7,8,10; Chen, Long-Qing4; Ikuhara, Yuichi11,12; Gao, Peng1,2,3,7

2018-05-25

10.1103/PhysRevB.97.180103

PHYSICAL REVIEW B   影响因子和分区

2469-9950

2469-9969

The effective screening of the polarization bound charge is a prerequisite to stabilize the ferroelectricity in ferroelectric thin films. Here, by combining annular bright field imaging and electron energy-loss spectroscopy (EELS) in an aberration-corrected scanning transmission electron microscope with phase-field simulations, we investigate the screening mechanism by quantitatively measuring the structural relaxation at Pb(Zr0.2Ti0.8)O-3/SrTiO3 interfaces. We find that the thickness of the interfacial layer is similar to 3.5 unit cells (similar to 1.4 nm) in a domain with upward polarization and similar to 5.5 unit cells (similar to 2.2 nm) in a domain with downward polarization. Phase-field simulations, an EELS analysis, and a lattice parameter analysis verify the existence of interfacial oxygen vacancies accounting for the narrower interfacial layer in the domain with upward polarization. Our study indicates the internal structural relaxation at the interface is the dominant mechanism for the polarization charge screening for ferroelectric films grown on insulating substrates and has implications for our understanding of domain switching in ferroelectric devices.

SCI ; EI

英语

其他

"Nanotechnology Platform" - MEXT, Japan[12024046]

Materials Science ; Physics

Materials Science, Multidisciplinary ; Physics, Applied ; Physics, Condensed Matter

WOS:000433061700002

AMER PHYSICAL SOC

20191906875334

Electron energy levels ; Electron scattering ; Energy dissipation ; Ferroelectric films ; Ferroelectric thin films ; Ferroelectricity ; Polarization ; Structural relaxation ; Transmission electron microscopy

Energy Losses (industrial and residential):525.4 ; Electricity: Basic Concepts and Phenomena:701.1 ; Dielectric Materials:708.1 ; Mechanics:931.1

PHYSICS

Web of Science

1.Peking Univ, Sch Phys, Electron Microscopy Lab, Beijing 100871, Peoples R China
2.Peking Univ, Sch Phys, Int Ctr Quantum Mat, Beijing 100871, Peoples R China
3.Peking Univ, Acad Adv Interdisciplinary Studies, Beijing 100871, Peoples R China
4.Penn State Univ, Dept Mat Sci & Engn, University Pk, PA 16802 USA
5.Natl Chung Hsing Univ, Dept Mat Sci & Engn, Taichung 40227, Taiwan
6.Natl Chiao Tung Univ, Dept Mat Sci & Engn, Hsinchu 30010, Taiwan
7.Collaborat Innovat Ctr Quantum Matter, Beijing 100871, Peoples R China
8.Peking Univ, Sch Phys, State Key Lab Mesoscop Phys, Beijing 100871, Peoples R China
9.Acad Sinica, Inst Phys, Taipei 11529, Taiwan
10.South Univ Sci & Technol China, Dept Phys, Shenzhen 518055, Peoples R China
11.Univ Tokyo, Inst Engn Innovat, Tokyo 1138656, Japan
12.Japan Fine Ceram Ctr, Nanostruct Res Lab, Nagoya, Aichi 4568587, Japan

Li, Mingqiang,Cheng, Xiaoxing,Li, Ning,et al. Atomic-scale mechanism of internal structural relaxation screening at polar interfaces[J]. PHYSICAL REVIEW B,2018,97(18).

Li, Mingqiang.,Cheng, Xiaoxing.,Li, Ning.,Liu, Heng-Jui.,Huang, Yen-Lin.,...&Gao, Peng.(2018).Atomic-scale mechanism of internal structural relaxation screening at polar interfaces.PHYSICAL REVIEW B,97(18).

Li, Mingqiang,et al."Atomic-scale mechanism of internal structural relaxation screening at polar interfaces".PHYSICAL REVIEW B 97.18(2018).