Phase-Field Model of Inhomogeneous Ferroelectric Crystals Under Ultrafast Stimuli

超快刺激下非均匀铁电晶体的相场模型

• 批准号: 1744213
• 负责人: Long-Qing Chen
• 金额: $ 33万
• 依托单位: Pennsylvania State Univ University Park
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 2018
• 资助国家: 美国
• 起止时间: 2018-09-01 至 2022-12-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1744213&HistoricalAwards=false
• 关键词: Phase; Field; Model; Inhomogeneous; Ferroelectric

NONTECHNICAL SUMMARYThis award supports theoretical research, computational modeling, and education that aim towards better understanding ferroelectric materials. Ferroelectrics comprise a class of crystalline materials that have found important technological applications in many types of devices, such as medical and underwater transducers, sensors, non-volatile memories, energy-efficient cooling. The goal of this research program is to develop the necessary materials theories and computer codes to understand how these ferroelectric crystals respond when subjected to external ultrafast stimuli, such as a sudden temperature rise or an electric-field pulse on their surface. The researchers will also explore possible new material states that may emerge as a result of such external stimulation. The group will utilize a network of experimental collaborators to validate the developed theory and computer codes against experiments. The developed theory and computer codes could find use in describing similar phenomena in other materials systems, for example the ultrafast magnetization dynamics in ferromagnetic materials for memory applications, and the potential formation of and transitions between novel electronic phases in electronic switching devices.The project is expected to have impact not only on materials science by advancing materials theories, but also on applied mathematics and the mechanics of materials. The PI will also integrate several educational and outreach activities into the research; these include: 1) the development of an open-source version of modeling software for materials and the organization of an associated annual workshop, 2) the recruitment of undergraduate students to perform research using the software package, and 3) the engagement of women and underrepresented minorities in STEM via participation in university-wide organized outreach activities and by recruiting them to perform research in the PI's laboratory.TECHNICAL SUMMARYThis award supports theoretical research, computational modeling, and education that aim towards better understanding ferroelectric materials. Ferroelectrics comprise a class of crystalline materials that have found important technological applications in many types of devices, such as medical and underwater transducers, sensors, non-volatile memories, energy-efficient cooling. The goal of this research program is to understand the dynamic responses of inhomogeneous ferroelectric crystals under external ultrafast stimuli and in the presence of complex electrostatic and elastic interactions among domains within the crystal. The PI and his group will develop a dynamical phase-field method to model, predict, and understand the dynamical spatiotemporal evolution of polarization and strain domain patterns under ultrafast stimuli, taking into account long-range electrostatic and elastic interactions and domain-wall energy. The group will also explore novel transient or metastable domain states that may emerge when an inhomogeneous crystal relaxes from its externally stimulated excited state back to the original or a new equilibrium state; these could be hidden states that are normally not observable under thermodynamic conditions. The researchers will investigate ferroelectric and piezoelectric responses of inhomogeneous crystals under ultrafast external stimuli, and will explore thermal, electric, mechanical, and multifunctional responses at ultrafast frequencies. The group will utilize a network of experimental collaborators to validate the developed theory and computer codes against experiments.The proposed dynamic phase-field method can be extended to the study of many other problems. For example, it can be adapted to solve a micromagnetic phase-field equation coupled with an elastodynamic equation for exploring ultrafast magnetization dynamics in ferromagnetic materials with strong magnetoelastic coupling. The proposed approach can also be extended to the study of electron-lattice coupling phenomena and the potential formation of novel electronic phases by introducing electronic degrees of freedom under ultrafast stimuli, allowing the manipulation of electronic phase transitions such as metal-insulator transitions in correlated systems.The project is expected to have impact not only on materials science by advancing materials theories, but also on applied mathematics and the mechanics of materials. The PI will also integrate several educational and outreach activities into the research; these include: 1) the development of an open-source version of modeling software for ferroic materials and the organization of an associated annual workshop, 2) the recruitment of undergraduate students to perform research using the software package, and 3) the engagement of women and underrepresented minorities in STEM via participation in university-wide organized outreach activities and by recruiting them to perform research in the PI's laboratory.This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.

非技术摘要该奖项支持旨在更好地了解铁电材料的理论研究、计算建模和教育。铁电体由一类晶体材料组成，在许多类型的设备中都有重要的技术应用，例如医疗和水下传感器、传感器、非易失性存储器、节能冷却。 该研究计划的目标是开发必要的材料理论和计算机代码，以了解这些铁电晶体在受到外部超快刺激（例如温度突然升高或表面电场脉冲）时如何响应。研究人员还将探索由于这种外部刺激而可能出现的新材料状态。该小组将利用实验合作者网络来根据实验验证所开发的理论和计算机代码。所开发的理论和计算机代码可用于描述其他材料系统中的类似现象，例如用于存储器应用的铁磁材料中的超快磁化动力学，以及电子开关器件中新型电子相的潜在形成和转变。该项目是预计不仅会通过推进材料理论对材料科学产生影响，还会对应用数学和材料力学产生影响。 PI 还将把一些教育和推广活动纳入研究中；其中包括：1) 开发材料建模软件的开源版本并组织相关的年度研讨会，2) 招募本科生使用该软件包进行研究，以及 3) 女性和女性的参与通过参加全校范围内组织的外展活动以及招募他们在 PI 实验室进行研究，在 STEM 中代表性不足的少数群体获得资助。技术摘要该奖项支持旨在更好地了解铁电材料的理论研究、计算建模和教育。铁电体由一类晶体材料组成，在许多类型的设备中都有重要的技术应用，例如医疗和水下传感器、传感器、非易失性存储器、节能冷却。该研究计划的目标是了解非均匀铁电晶体在外部超快刺激下以及晶体内域之间存在复杂的静电和弹性相互作用的情况下的动态响应。 PI和他的团队将开发一种动态相场方法来建模、预测和理解超快刺激下极化和应变域模式的动态时空演化，同时考虑到长程静电和弹性相互作用以及域壁能量。该小组还将探索当非均匀晶体从外部刺激的激发态松弛回到原始或新的平衡态时可能出现的新的瞬态或亚稳态域状态；这些可能是在热力学条件下通常无法观察到的隐藏状态。研究人员将研究非均质晶体在超快外部刺激下的铁电和压电响应，并将探索超快频率下的热、电、机械和多功能响应。该小组将利用实验合作者网络来验证所开发的理论和计算机代码的实验。所提出的动态相场方法可以扩展到许多其他问题的研究。例如，它可以适用于求解与弹性动力学方程相结合的微磁相场方程，以探索具有强磁弹性耦合的铁磁材料中的超快磁化动力学。通过在超快刺激下引入电子自由度，所提出的方法还可以扩展到电子晶格耦合现象和新型电子相的潜在形成的研究，从而允许操纵电子相变，例如相关系统中的金属-绝缘体转变该项目预计不仅会通过推进材料理论对材料科学产生影响，还会对应用数学和材料力学产生影响。 PI 还将把一些教育和推广活动纳入研究中；其中包括：1) 开发铁质材料建模软件的开源版本并组织相关的年度研讨会，2) 招募本科生使用该软件包进行研究，以及 3) 女性的参与通过参与全校范围内组织的外展活动以及招募他们在 PI 实验室进行研究，该奖项反映了 NSF 的法定使命，并通过使用基金会的智力优势和更广泛的评估进行评估，被认为值得支持影响审查标准。

项目成果

Mechanically induced ferroelectric switching in BaTiO3 thin films

• DOI: 10.1016/j.actamat.2020.04.032
• 发表时间: 2020-07-01
• 期刊: ACTA MATERIALIA
• 影响因子: 9.4
• 作者: Wang, Bo;Lu, Haidong;Chen, Long-Qing
• 通讯作者: Chen, Long-Qing

Mechanically controllable nonlinear dielectrics

• DOI: 10.1126/sciadv.aaz3180
• 发表时间: 2020-03
• 期刊: Science Advances
• 影响因子: 13.6
• 作者: D. Ko;M. Tsai;Jhih Wei Chen;P. Shao;Y. Tan;Jing Wang;Sheng-Zhu Ho;Yu-Hong Lai;Y. Chueh

Observation of Unconventional Dynamics of Domain Walls in Uniaxial Ferroelectric Lead Germanate

• DOI: 10.1002/adfm.202000284
• 发表时间: 2020-03
• 期刊: Advanced Functional Materials
• 影响因子: 19
• 作者: O. Bak;T. S. Holstad;Yueze Tan;Haidong Lu;D. Evans;K. Hunnestad;Bo Wang;J. McConville;P. Becker;L. Bohatý;I. Lukyanchuk;V. Vinokur;A. V. van Helvoort;J. Gregg;Long-qing Chen;D. Meier;A. Gruverman

Enhanced flexoelectricity at reduced dimensions revealed by mechanically tunable quantum tunnelling

• DOI: 10.1038/s41467-019-08462-0
• 发表时间: 2019-02-01
• 期刊: NATURE COMMUNICATIONS
• 影响因子: 16.6
• 作者: Das, Saikat;Wang, Bo;Noh, Tae Won
• 通讯作者: Noh, Tae Won

First-principles calculations of domain wall energies of prototypical ferroelectric perovskites

原型铁电钙钛矿磁畴壁能量的第一性原理计算

• DOI: 10.1016/j.actamat.2022.118351
• 发表时间: 2023
• 期刊: Acta Materialia
• 影响因子: 9.4
• 作者: Zhang, Xueyou;Wang, Bo;Ji, Yanzhou;Xue, Fei;Wang, Yi;Chen, Long-Qing;Nan, Ce-Wen
• 通讯作者: Nan, Ce-Wen