Zheng Yu, Liu Lei, Nan Hanqing, Shen Zhen-Xiong, Zhang Ge, Chen Duyu, He Lixin, Xu Wenxiang, Chen Mohan, Jiao Yang, Zhuang Houlong
Department of Physics, Arizona State University,Tempe, AZ 85287, USA.
School for Engineering of Matter, Transport and Energy, Arizona State University, Tempe, AZ 85287, USA.
Sci Adv. 2020 Apr 17;6(16):eaba0826. doi: 10.1126/sciadv.aba0826. eCollection 2020 Apr.
Disordered hyperuniformity (DHU) is a recently proposed new state of matter, which has been observed in a variety of classical and quantum many-body systems. DHU systems are characterized by vanishing infinite-wavelength normalized density fluctuations and are endowed with unique novel physical properties. Here, we report the discovery of disordered hyperuniformity in atomic-scale two-dimensional materials, i.e., amorphous silica composed of a single layer of atoms, based on spectral-density analysis of high-resolution transmission electron microscopy images. Moreover, we show via large-scale density functional theory calculations that DHU leads to almost complete closure of the electronic bandgap compared to the crystalline counterpart, making the material effectively a metal. This is in contrast to the conventional wisdom that disorder generally diminishes electronic transport and is due to the unique electron wave localization induced by the topological defects in the DHU state.
无序超均匀性（DHU）是最近提出的一种新的物质状态，已在各种经典和量子多体系统中被观察到。DHU系统的特征是无限波长归一化密度涨落消失，并具有独特的新颖物理性质。在此，我们基于高分辨率透射电子显微镜图像的光谱密度分析，报告了在原子尺度二维材料（即由单层原子组成的非晶硅）中发现无序超均匀性。此外，我们通过大规模密度泛函理论计算表明，与晶体对应物相比，DHU导致电子带隙几乎完全闭合，使该材料有效地成为一种金属。这与传统观念相反，传统观念认为无序通常会削弱电子传输，这是由于DHU状态下拓扑缺陷引起的独特电子波局域化所致。
