Article
Materials Science, Multidisciplinary
Pavel Marton, Mauro A. P. Goncalves, Marek Pasciak, Sabine Koerbel, Venceslav Chumchal, Martin Plesinger, Antonin Klic, Jirka Hlinka
Summary: We conducted a theoretical investigation on a charged 180 degrees domain wall in ferroelectric PbTiO3, compensated by randomly distributed immobile charge defects, using atomistic shell-model simulations and continuous phase-field simulations. Our predictions show that the domain walls form a zigzag pattern, accompanied by local polarization rotation, which provides an efficient mechanism for charge compensation.
Article
Chemistry, Multidisciplinary
Lutz Baumgarten, Thomas Szyjka, Terence Mittmann, Andrei Gloskovskii, Christoph Schlueter, Thomas Mikolajick, Uwe Schroeder, Martina Mueller
Summary: The reliability of ferroelectric HfO2- and HZO-based memory devices is strongly influenced by the choice of electrode materials. Interface conditions, such as band alignment, defect formation, and doping, are recognized as decisive factors for device performance. Hard X-ray photoelectron spectroscopy reveals two opposite scenarios of band alignment in TiN/HZO/TiN and IrO2/HZO/IrO2, explaining the conditions for stable device performance and degradation. A key condition for the stability of ferroelectric devices is identified as the alignment of the charge neutrality level with the metallic Fermi level. Oxygen-deficient HfO2-based interfaces, where the Fermi level of the metal electrode is close to the conduction band of the ferroelectric insulator, can achieve stable device performance.
ADVANCED FUNCTIONAL MATERIALS
(2023)
Article
Materials Science, Multidisciplinary
J. Gosteau, R. Arras, P. Chen, H. J. Zhao, C. Paillard, L. Bellaiche
Summary: This study investigates the spin-orbit effects in strained PbTiO3 using first-principles calculations, tight-binding approach, and a k . p model. It shows that strain can rotate the electrical polarization of PbTiO3 and significantly affect the spin-splitting parameters of Ti d-state conduction bands. Additionally, a quasipersistent spin texture with d(yz-zx) character was identified in the orthorhombic phase, suggesting strain as a potential method for tuning spin-orbit effects in ferroelectric materials.
Article
Chemistry, Multidisciplinary
Y. P. Feng, R. J. Jiang, Y. L. Zhu, Y. L. Tang, Y. J. Wang, M. J. Zou, W. R. Geng, X. L. Ma
Summary: This study investigates the strain field of ferroelastic domains and misfit dislocations in perovskite ferroelectric thin films using advanced aberration-corrected transmission electron microscopy combined with geometry phase analysis. The results reveal in-plane strain and lattice rotation, and polarization rotation phenomenon in the thin films.
Article
Chemistry, Physical
Jian Shi, Chunying Chao, Yingying Gao, Hao Li, Suxiang Ge, Caixia Li, Xi Chen, Weiwei He
Summary: Designing an architecture that introduces oxygen vacancies (OVs) in ferroelectric materials without weakening the ferroelectric polarization has a positive effect on separating and inhibiting recombination of photogenerated carriers. This study reported an indirect strategy to form PTO@BiOCl-OVs heterojunction nanoplates by introducing BiOCl rich in OVs into the positive surface of ferroelectrics via a simple hydrothermal method and UV light irradiation. The 3% PTO@BiOCl-OVs heterojunction nanoplates showed excellent photocatalytic activity for RhB degradation under visible light. ESR signals confirmed the presence of reactive species such as O-2(-), center dot OH, and O-1(2).
APPLIED SURFACE SCIENCE
(2023)
Article
Chemistry, Multidisciplinary
Zhaohui Ren, Luoyuan Ruan, Lichang Yin, Karthik Akkiraju, Livia Giordano, Zhongran Liu, Shi Li, Zixing Ye, Songda Li, Hangsheng Yang, Yong Wang, He Tian, Gang Liu, Yang Shao-Horn, Gaorong Han
Summary: It is reported that surface oxygen vacancies can be confined electrostatically near the perimeter interface between Pt {111} nanocrystals and the negative polar surface (001) of ferroelectric PbTiO3. This catalyst demonstrates tunable catalytic CO oxidation kinetics by increasing the O-2 gas pressure, opening a new pathway for CO oxidation catalytic activity.
ADVANCED MATERIALS
(2022)
Article
Nanoscience & Nanotechnology
Celine Lichtensteiger, Marios Hadjimichael, Edoardo Zatterin, Chia-Ping Su, Iaroslav Gaponenko, Ludovica Tovaglieri, Patrycja Paruch, Alexandre Gloter, Jean-Marc Triscone
Summary: We investigate the ferroelastic/ferroelectric domain structure in PbTiO3 epitaxially strained on (110)(o)-oriented DyScO3 substrates. The anisotropic strain created by the orthorhombic substrate results in an asymmetry in the domain configuration, with domain walls aligned along one of the two in-plane directions. The periodicity of the film thickness deviates from the Kittel law, and the domain configuration transitions from flux-closure to a/c-phase as the thickness increases, forming larger superdomains.
Article
Materials Science, Multidisciplinary
Zhaoming Fu, Haotian Chen, Yingkai Liu, Meng Liu, Wu-Ming Liu
Summary: The study explores the ferroelectric effects and spin-polarized 2DEG (or 2DHG) in the BiFeO3/SrTiO3 heterostructure. Theoretical simulations show various physical phenomena such as ferroelectric domains, monodirectional polarization, and spin-polarized 2DEGs (or 2DHGs) at domain walls. The identified spin-polarized 2DEGs (or 2DHGs) are discussed for their potential importance in fundamental research and applications.
Article
Chemistry, Multidisciplinary
Thomas M. Linker, Ken-ichi Nomura, Shogo Fukushima, Rajiv K. Kalia, Aravind Krishnamoorthy, Aiichiro Nakano, Kohei Shimamura, Fuyuki Shimojo, Priya Vashishta
Summary: We have developed a method called NNQMD-BEC, which combines electric-field dynamics with the Born effective charge (BEC) to extend the Neural Network Quantum Molecular Dynamics (NNQMD) simulation method. We validated NNQMD-BEC for the switching mechanisms of classic ferroelectric PbTiO(3) bulk crystal and 180° domain walls. Our simulations accurately describe the nucleation and growth mechanism during domain wall switching. In triaxially strained PbTiO3 with common strain conditions in many superlattice configurations, we observed the induction of a flux-closure texture with the application of an electric field perpendicular to the original polarization direction.
Article
Physics, Applied
Yushui Tian, Yulu Zhou, Miao Zhao, Yifang Ouyang, Xiaoma Tao
Summary: The effect of VB metal doping HfO2 and a metal co-doping method based on electronic compensation to regulate oxygen defects and improve ferroelectricity in HfO2-based ferroelectric thin films are studied. The results show that co-doping with Sc-Nb and Sc-Ta is an effective method to enhance ferroelectricity in HfO2.
APPLIED PHYSICS LETTERS
(2023)
Article
Physics, Applied
Yi-Jan Lin, Chih-Yu Teng, Chenming Hu, Chun-Jung Su, Yuan-Chieh Tseng
Summary: This paper proposes an approach to enhance Hf0.5Zr0.5O2 (HZO) ferroelectric orthorhombic phase formation through in situ NH3 plasma treatment. The treatment suppresses interfacial diffusion between HZO and the top TiN electrode, reducing oxygen vacancies within HZO. The results demonstrate improved reliability and ferroelectric performance of HZO devices with stable transfer characteristics and memory windows after NH3 treatment.
APPLIED PHYSICS LETTERS
(2021)
Article
Engineering, Electrical & Electronic
Pragyanand Prajapati, Akhilesh Kumar Singh
Summary: By doping molybdenum in lead titanate, we have achieved a significant reduction in the band gap of the material without reducing its polarization, making it an ideal photovoltaic material for solar energy harvesting. Our research also found that molybdenum doping enhances conductivity, facilitating the transport of charge carriers.
JOURNAL OF MATERIALS SCIENCE-MATERIALS IN ELECTRONICS
(2022)
Article
Chemistry, Physical
Denis Alikin, Alexander Abramov, Anton Turygin, Anton Ievlev, Victoria Pryakhina, Dmitry Karpinsky, Qingyuan Hu, Li Jin, Vladimir Shur, Alexander Tselev, Andrei Kholkin
Summary: A novel method based on switching spectroscopy piezoresponse force microscopy (SSPFM) is proposed for probing subsurface charged defects in ferroelectric materials with nanometer-scale spatial resolution. Compared with composition-sensitive methods, SSPFM shows high sensitivity to electric potential variations from charged defects. It also demonstrates the capability to evaluate dynamics of polarization screening caused by charged defects, which is of significant interest for understanding defect-mediated processes in ferroelectrics.
Article
Chemistry, Multidisciplinary
Shuguan Li, Fang Chen, Shengqi Chu, Zeyu Zhang, Jindi Huang, Shengyao Wang, Yibo Feng, Cong Wang, Hongwei Huang
Summary: This study develops a coupled strategy of ferroelectric poling and cationic vacancy to achieve high-performance CO2 photoreduction on ferroelectric Bi2MoO6, and discloses their interesting synergy-compensation relationship. The corona poling enhances the intrinsic electric field for charge separation, while the introduced Mo vacancy facilitates the adsorption and activation of CO2 by creating local electric field. Coupling poling and V-Mo not only integrates their advantages but also compensates for their shortcomings.
Article
Physics, Applied
Sujoy Saha, Ram Prakash Singh, Ashish Rout, Aditya Mishra, Amanat Ali, Himalay Basumatary, Rajeev Ranjan
Summary: There is a growing interest in BiFeO3-based alloys for their potential in developing high-temperature high-performance piezoelectric materials and interesting multiferroic properties. Ceramics synthesized with additives, such as MnO2, exhibit stabilized ferromagnetism caused by the precipitation of trace amounts of ferrimagnetic phases not easily detected by conventional x-ray diffraction measurements. These findings not only provide a strategy for developing magnetoelectric multiferroic composites, but also contribute to a better understanding of the electromechanical response in BiFeO3-based alloys.
JOURNAL OF APPLIED PHYSICS
(2023)