Terahertz optics-driven phase transition in two-dimensional multiferroics
Terahertz optics-driven phase transition in two-dimensional multiferroics
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DOI：
10.1038/s41699-020-00189-7
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发表时间：
2020-11
影响因子：
9.7
通讯作者：
Jian Zhou;Shunhong Zhang
中科院分区：
文献类型：
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作者：
Jian Zhou;Shunhong Zhang
位移马氏体相变在具有快速开关速度的基于晶闸管的数据存储应用中具有潜在的前景。除了传统的相变材料外，最近发现的二维铁磁材料由于其快速的铁磁开关动力学而受到广泛关注，这可以极大地提高数据存储密度和提高读/写速度。在这项研究中，我们提出了一个太赫兹激光与中等强度和选定的频率可以触发铁性有序开关的二维多铁性，这是一个无损伤的非接触的方法。通过第一性原理计算，我们从理论上和计算上研究了两种实验制备的多铁性（铁电和铁弹）材料β-GeSe和α-SnTe单层膜的光致电子、声子和力学响应.我们表明，不同的取向变量的相对稳定性，可以有效地操纵通过太赫兹激光，这是选择性和强烈耦合的横向光学声子模式的偏振方向。从一种取向变体到另一种取向变体的转变可以是无势垒的，表明超快转变动力学和常规成核-生长相变过程是可以避免的。
Displacive martensitic phase transition is potentially promising in semiconductor-based data storage applications with fast switching speed. In addition to traditional phase transition materials, the recently discovered two-dimensional ferroic materials are receiving a lot of attention owing to their fast ferroic switching dynamics, which could tremendously boost data storage density and enhance read/write speed. In this study, we propose that a terahertz laser with an intermediate intensity and selected frequency can trigger ferroic order switching in two-dimensional multiferroics, which is a damage-free noncontacting approach. Through first-principles calculations, we theoretically and computationally investigate optically induced electronic, phononic, and mechanical responses of two experimentally fabricated multiferroic (with both ferroelastic and ferroelectric) materials,β-GeSe andα-SnTe monolayer. We show that the relative stability of different orientation variants can be effectively manipulated via the polarization direction of the terahertz laser, which is selectively and strongly coupled with the transverse optical phonon modes. The transition from one orientation variant to another can be barrierless, indicating ultrafast transition kinetics and the conventional nucleation-growth phase transition process can be avoidable.