威斯康星大学麦迪逊分校Song Jin小组取得一项新突破。他们的最新研究提出了在非欧几里得的表面生长超扭曲螺旋层材料。 该项研究成果发表在2020年10月23日出版的《科学》上。

该研究组提出一个通用模型描述具有螺旋位错螺旋的分层材料在非欧几里得的表面的生长，结果表明，它会产生连续扭曲的多层超结构。超扭曲螺旋的二硫化钨(WS2)和二硒化钨(WSe2)在螺旋中心附近垂悬在纳米颗粒上生长，从而实验证明了该模型。微观结构分析表明，晶格扭曲与层的几何扭曲一致，从而导致原子层之间出现莫尔超晶格。

据介绍，欧几里得几何是经典结晶学的基本数学框架。传统上，分层材料生长在平面基板上；在非欧几里得表面生长欧几里得晶体仍然很少被研究。

附：英文原文

Title: Supertwisted spirals of layered materials enabled by growth on non-Euclidean surfaces

Author: Yuzhou Zhao, Chenyu Zhang, Daniel D. Kohler, Jason M. Scheeler, John C. Wright, Paul M. Voyles, Song Jin

Issue&Volume: 2020/10/23

Abstract: Euclidean geometry is the fundamental mathematical framework of classical crystallography. Traditionally, layered materials are grown on flat substrates; growing Euclidean crystals on non-Euclidean surfaces has rarely been studied. We present a general model describing the growth of layered materials with screw-dislocation spirals on non-Euclidean surfaces and show that it leads to continuously twisted multilayer superstructures. This model is experimentally demonstrated by growing supertwisted spirals of tungsten disulfide (WS2) and tungsten diselenide (WSe2) draped over nanoparticles near the centers of spirals. Microscopic structural analysis shows that the crystal lattice twist is consistent with the geometric twist of the layers, leading to moiré superlattices between the atomic layers.

DOI: 10.1126/science.abc4284

Source: https://science.sciencemag.org/content/370/6515/442