Elucidating the Physics of Flexoelectricity Through First-Principles Calculations of Complex Materials

通过复杂材料的第一性原理计算阐明挠曲电的物理原理

基本信息

批准号：
1918455
负责人：
Cyrus Dreyer
金额：
$ 33.35万
依托单位：
SUNY at Stony Brook
依托单位国家：
美国
项目类别：
Standard Grant
财政年份：
2019
资助国家：
美国
起止时间：
2019-12-15 至 2022-11-30
项目状态：
已结题

来源：
https://www.nsf.gov/awardsearch/showAward?AWD_ID=1918455&HistoricalAwards=false
关键词：
Elucidating Physics Flexoelectricity Through First

项目摘要

NONTECHNICAL SUMMARYThis award supports computational and theoretical research, and education on flexoelectricity.If a strain gradient is applied to a piece of an electrically insulating material, for example by bending it, a voltage will be created across the material. This effect, known as flexoelectricity, has attracted attention because of the possibility for technological applications such as actuators, deflection sensors, and energy harvesters. Also, flexoelectricity is important since modern nanoscale electronic devices may contain large unintentional strain gradients, and thus flexoelectricity may play a crucial role in their properties. A pivotal missing ingredient in developing a quantitative understanding of flexoelectricity has been the lack of an efficient and accurate computational methodology to predict the flexoelectric response of a material. In this project, the PI will build on predictive methodology he has developed with collaborators and apply it to explore and characterize the flexoelectric response in materials more complex than could be theoretically investigated before. The goal of this research is to better understand what materials properties lead to an especially large flexoelectric response, which can be utilized for technological applications. This will also help identify materials with a suppressed flexoelectric response, which will be useful in cases where the effects of unintentional strain gradients need to be mitigated. The research activities in this project serve as an ideal platform for the education and mentoring of graduate and undergraduate students in diverse aspects of condensed matter physics, materials science, and computational science. TECHNICAL SUMMARYThis award supports computational and theoretical research, and education on flexoelectricity.The flexoelectric effect, where electrical polarization is induced by a strain gradient, is universal in all insulators. As devices shrink to the micro and nanoscale, large strain gradients can occur, and therefore the flexoelectric effect may play a significant role in their properties. Also, flexoelectricity can be exploited for novel paradigms of electromechanical manipulation of materials, such as the development of piezoelectric "metamaterials" constructed from nonpiezoelectric constituents, or mechanical switching of ferroelectric polarization. In this work, the PI will explore and elucidate the physics of flexoelectricity in complex materials, utilizing recently developed density functional perturbation theory methodology for accurately and efficiently calculating flexoelectric coefficients. The PI will investigate the flexoelectric response in two materials systems with the goal of addressing significant open questions relating to how flexoelectricity is generally manifested in materials. The PI will focus on two-dimensional, van der Waals bonded materials including, boron nitride and the transition-metal dichalcogenides, and "distorted" perovskite oxides with lower symmetry than the cubic parent structure. The PI will systematically explore how symmetry, mechanical, and dielectric properties influence the flexoelectric response, and how this response can be measured or manipulated by forming heterostructures or superlattices, or modifying surface properties. The materials study performed in this work, will enable the identification of specific materials and material systems that have large flexoelectric responses which may be useful for applications, as well as those with small responses, which are necessary in applications where gradients are present unintentionally and flexoelectricity must be mitigated.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弯曲电学的计算和理论研究以及教育。如果将应变梯度应用于一块电绝缘材料（例如通过弯曲它），则会在材料上产生电压。这种被称为挠曲电的效应因其在执行器、偏转传感器和能量收集器等技术应用中的可能性而引起了人们的关注。此外，弯曲电性也很重要，因为现代纳米级电子器件可能包含大的无意应变梯度，因此弯曲电性可能在其性能中发挥至关重要的作用。在对挠曲电进行定量理解时，一个关键的缺失因素是缺乏有效且准确的计算方法来预测材料的挠曲电响应。在这个项目中，PI 将建立在他与合作者开发的预测方法的基础上，并将其应用于探索和表征比以前理论上研究更复杂的材料中的挠曲电响应。这项研究的目的是更好地了解哪些材料特性会导致特别大的挠曲电响应，从而可用于技术应用。这也将有助于识别具有抑制挠曲电响应的材料，这在需要减轻意外应变梯度影响的情况下非常有用。该项目的研究活动为凝聚态物理、材料科学和计算科学各个方面的研究生和本科生的教育和指导提供了一个理想的平台。技术摘要该奖项支持弯曲电学的计算和理论研究以及教育。弯曲电效应（即由应变梯度引起的电极化）在所有绝缘体中普遍存在。随着器件缩小到微米和纳米尺度，可能会出现大的应变梯度，因此挠曲电效应可能对其性能发挥重要作用。此外，挠曲电还可用于材料机电操纵的新范例，例如开发由非压电成分构造的压电“超材料”，或铁电极化的机械切换。在这项工作中，PI 将探索和阐明复杂材料中的挠曲电物理原理，利用最近开发的密度泛函微扰理论方法来准确有效地计算挠曲电系数。 PI 将研究两种材料系统中的挠曲电响应，目的是解决与挠曲电通常如何在材料中表现相关的重大开放性问题。 PI将重点研究二维范德华键合材料，包括氮化硼和过渡金属二硫属化物，以及对称性低于立方母体结构的“扭曲”钙钛矿氧化物。 PI 将系统地探索对称性、机械和介电特性如何影响挠曲电响应，以及如何通过形成异质结构或超晶格或修改表面特性来测量或操纵这种响应。这项工作中进行的材料研究将能够识别具有大挠曲电响应的特定材料和材料系统，这可能对应用有用，以及具有小响应的材料和材料系统，这在无意中存在梯度和挠曲电的应用中是必要的该奖项反映了 NSF 的法定使命，并通过使用基金会的智力价值和更广泛的影响审查标准进行评估，被认为值得支持。

项目成果

期刊论文数量（12）

专著数量（0）

科研奖励数量（0）

会议论文数量（0）

专利数量（0）

Long-range quadrupole electron-phonon interaction from first principles

DOI：
10.1103/physrevb.102.125203
发表时间：
2020-03
期刊：
Physical Review B
影响因子：
3.7
作者：
Jinsoo Park;Jin-Jian Zhou;V. Jhalani;C. Dreyer;M. Bernardi
通讯作者：
Jinsoo Park;Jin-Jian Zhou;V. Jhalani;C. Dreyer;M. Bernardi

Correlation-induced octahedral rotations in SrMoO3

DOI：
10.1103/physrevb.104.035102
发表时间：
2021-07-01
期刊：
PHYSICAL REVIEW B
影响因子：
3.7
作者：
Hampel, Alexander;Lee-Hand, Jeremy;Dreyer, Cyrus E.
通讯作者：
Dreyer, Cyrus E.

Cooperative Interactions between Surface Terminations Explain Photocatalytic Water Splitting Activity on SrTiO3

表面终止之间的协同相互作用解释了 SrTiO3 上的光催化水分解活性

DOI：
10.1103/prxenergy.1.023002
发表时间：
2022
期刊：
PRX Energy
影响因子：
0
作者：
Sharma, Vidushi;Bein, Benjamin;Lai, Amanda;Pamuk, Betül;Dreyer, Cyrus E.;Fernández-Serra, Marivi;Dawber, Matthew
通讯作者：
Dawber, Matthew

Quantum embedding methods for correlated excited states of point defects: Case studies and challenges

DOI：
10.1103/physrevb.105.235104
发表时间：
2021-05
期刊：
Physical Review B
影响因子：
3.7
作者：
Lukas Muechler;D. I. Badrtdinov;A. Hampel;Jennifer Cano;M. Rösner;C. Dreyer
通讯作者：
Lukas Muechler;D. I. Badrtdinov;A. Hampel;Jennifer Cano;M. Rösner;C. Dreyer

First-principles study of the electronic, magnetic, and crystal structure of perovskite molybdates

钙钛矿钼酸盐的电子、磁性和晶体结构的第一性原理研究