近日，美国宾夕法尼亚大学的Ritesh Agarwal及其研究小组与印度科学研究所的Pavan Nukala等人合作，对铁性In2Se3中的电驱动长程固态非晶化进行了研究。相关研究成果已于2024年11月6日在国际权威学术期刊《自然》上发表。

本文报道了一种节能且非常规的长程固态非晶化现象，该现象是通过在硒化铟纳米线的新型铁性β″相上，施加直流偏置而非脉冲电刺激实现的。施加的电场垂直于极化方向，电流平行于范德华层流动，同时产生压电应力，这三者之间的复杂相互作用导致该层状材料中，形成了层间滑动缺陷和由面内极化旋转引起的耦合无序。

当电致无序达到临界极限时，结构会变得不稳定并局部坍塌成非晶相，这一现象通过声猝发在更大的微观长度尺度上重复出现。这项研究工作揭示了材料中铁性有序结构与外部施加的电场、电流以及内部产生的应力之间，此前未知的多模耦合机制，对于设计用于低功耗电子和光子应用的新型材料和器件，具有实用价值。

据悉，电致非晶化现象并不常见，迄今为止仅通过脉冲电流在少数几种材料体系中实现，且这些体系大多基于熔融-淬火过程。然而，如果能够避免熔融步骤，并通过电学方式实现固态非晶化，那么这将为低功耗器件应用开辟新的可能性。

附：英文原文

Title: Electrically driven long-range solid-state amorphization in ferroic In2Se3

Author: Modi, Gaurav, Parate, Shubham K., Kwon, Choah, Meng, Andrew C., Khandelwal, Utkarsh, Tullibilli, Anudeep, Horwath, James, Davies, Peter K., Stach, Eric A., Li, Ju, Nukala, Pavan, Agarwal, Ritesh

Issue&Volume: 2024-11-06

Abstract: Electrically induced amorphization is uncommon and has so far been realized by pulsed electrical current in only a few material systems, which are mostly based on the melt–quench process. However, if the melting step can be avoided and solid-state amorphization can be realized electrically, it opens up the possibility for low-power device applications. Here we report an energy-efficient, unconventional long-range solid-state amorphization in a new ferroic β″-phase of indium selenide nanowires through the application of a direct-current bias rather than a pulsed electrical stimulus. The complex interplay of the applied electric field perpendicular to the polarization, current flow parallel to the van der Waals layer and piezoelectric stress results in the formation of interlayer sliding defects and coupled disorder induced by in-plane polarization rotation in this layered material. On reaching a critical limit of the electrically induced disorder, the structure becomes frustrated and locally collapses into an amorphous phase, and this phenomenon is replicated over a much larger microscopic-length scale through acoustic jerks. Our work uncovers previously unknown multimodal coupling mechanisms of the ferroic order in materials to the externally applied electric field, current and internally generated stress, and can be useful to design new materials and devices for low-power electronic and photonic applications.

DOI: 10.1038/s41586-024-08156-8

Source: https://www.nature.com/articles/s41586-024-08156-8