Engineering nanoscale polarization at the SrTiO3/Ge interface

SCRIPTA MATERIALIA

卷:178

Article

Le, Tony^1,2  Kurt, Onur¹  Ouyang, Jun¹  Wang, Jianjun³  Chen, Long-Qing³  Lin, Edward L.⁴  Ekerdt, John G.⁴  Ren, Yuhang^1,2 

[1] CUNY, Hunter Coll, Phys & Astron, 695 Pk Ave, New York, NY 10065 USA

[2] CUNY, Grad Ctr, 365 5th Ave, New York, NY 10016 USA

[3] Penn State Univ, Mat Res Inst, University Pk, PA 16802 USA

[4] Univ Texas Austin, McKetta Dept Chem Engn, Austin, TX 78712 USA

关键词: Nanoelectronics;    Electric polarization;    Second harmonics generation;    Interface ferroelectricity;    Phase field simulation;   

DOI  :  10.1016/j.scriptamat.2019.12.033

来源: Elsevier

【 摘 要 】

The ability to manipulate electric polarization at reduced dimension has recently generated intense research interests. Here, we report the engineering of interfacial ferroelectricity by the monolithic integration of a single crystalline SrTiO3 (STO) film on a germanium Ge(001) substrate. A combination of nonlinear optical measurements, microstructural analyses, and phase-field simulations provide evidences of room-temperature ferroelectricity in the epitaxial STO ultrathin film. We show that the collective atomic displacements of Ti near the STO/Ge interface are responsible for the generation of an in-plane ferroelectric polarization. An a(1)/a(2) domain pattern with a stable net polarization along the [110] in-plane direction is revealed. (C) 2019 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.

【 授权许可】

Free