《材料科學論壇》學術報告

時間：2021年3月18日，下午15:00-16:40
地點：主樓東配樓二層228會議室
題目：First-principles study of ferroelectricity and magnetoelectric effects in complex oxides
報告人：葉萌
聯系人：朱靜

摘要：
鐵電材料在作為存儲單元、傳感器和晶體管方面有着廣闊的應用。第一性原理計算在預測鐵電行為方面取得了巨大的成功，加深了對極化機制的理解。本次報告将介紹鐵電極化相關的重要概念以及一些重要的研究方法，并以幾種典型材料為例說明第一性原理計算如何揭示鐵電極化的機理。另外，報告還會以波恩有效電荷的概念作為類比，介紹動态磁電荷的概念（dynamical magnetic charge）。這一概念在理解磁電耦合機制方面有着十分重要的作用，同時報告将從理論研究出發介紹能夠增強動态磁電荷，在材料中獲得強磁電耦合效應的方法。
Ferroelectric (FE) materials are of fundamental interest and have broad applications as memory cells, sensors and transistors. First-principles methods have achieved great success in the prediction of polarization and have provided great insight in the understanding of FE mechanisms. In this talk, I will give a review of important concepts and methods in describing ferroelectricity and using several materials as examples to demonstrate how first-principles calculations can reveal the mechanism of ferroelectricity. In addition, I will also extend the concept of Born effective charge Ze to its magnetic analogue, the dynamical magnetic charge Zm. The concept of magnetic charges plays an important role in understanding the magnetoelectric couplings and I will present theoretical studies of the mechanisms that could enhance the magnetic charge Zm.

報告人簡介：
葉萌，清華大學物理系水木學者。2011年本科畢業于中國科學技術大學，2016年獲得羅格斯大學物理學博士學位，導師為David Vanderbilt教授。2016至2019年在芝加哥大學從事博士後研究，導師為Giulia Galli教授。她的研究主要聚焦于材料中極化、磁性、光學性質之間的耦合效應，特别是在鐵電材料、多鐵材料、固态自旋量子比特和非線性光學材料方面有着深入的研究。
Meng Ye is currently a Shuimu Tsinghua Scholar in the physics department of Tsinghua University. She graduated from the University of Science and Technology of China in 2011 and received her Ph.D degree in physics from Rutgers University under the supervision of Professor David Vanderbilt in 2016. After that, she went to the University of Chicago to work with Prof. Giulia Galli as a postdoc scholar from 2016 to 2019. She has broad interests in theoretical and computational condensed matter physics. Her research is focused on the cross-coupling of polarization, magnetization and light in materials, especially in ferroelectrics, multiferroics, solid state spin qubits and non-linear optical materials.