Observation of single-defect memristor in an MoS2 atomic sheet
Observation of single-defect memristor in an MoS2 atomic sheet
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DOI：
10.1038/s41565-020-00789-w
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发表时间：
2020-11-09
影响因子：
38.3
通讯作者：
Akinwande, Deji
中科院分区：
文献类型：
--
作者：
Hus, Saban M.;Ge, Ruijing;Akinwande, Deji
非易失性电阻开关，也称为忆阻器 (1) 效应，即电场切换两端器件的电阻状态，已成为高密度信息存储、计算和可重构系统开发中的一个重要概念(2-9)。过去十年见证了金属氧化物和固体电解质等非易失性电阻开关材料的巨大进步。长期以来，人们一直认为漏电流会阻止在纳米薄绝缘层中观察到这种现象。然而，最近在过渡金属二硫属化物 (10,11) 和六方氮化硼 (12) 夹层结构（也称为原子电阻器）的二维单层中发现的非易失性电阻开关驳斥了这一观点，并由于尺寸缩放的好处而增加了新的材料维度 (10,13)。在这里，我们使用单层 MoS2 作为模型系统阐明了原子片中切换机制的起源。原子成像和光谱表明，金属取代硫空位会导致电阻发生非挥发性变化，缺陷结构和电子态的计算研究证实了这一点。这些发现提供了对非易失性开关的原子理解，并为精确缺陷工程开辟了新方向，直至单个缺陷，以实现用于超密集存储器、神经形态计算和射频通信系统应用的最小忆阻器(2,3,11)。原子成像和光谱学的结合揭示了金属取代硫空位是过渡金属二硫属化物单层中电阻开关的基本机制。
Non-volatile resistive switching, also known as memristor(1) effect, where an electric field switches the resistance states of a two-terminal device, has emerged as an important concept in the development of high-density information storage, computing and reconfigurable systems(2-9). The past decade has witnessed substantial advances in non-volatile resistive switching materials such as metal oxides and solid electrolytes. It was long believed that leakage currents would prevent the observation of this phenomenon for nanometre-thin insulating layers. However, the recent discovery of non-volatile resistive switching in two-dimensional monolayers of transition metal dichalcogenide(10,11) and hexagonal boron nitride(12) sandwich structures (also known as atomristors) has refuted this belief and added a new materials dimension owing to the benefits of size scaling(10,13). Here we elucidate the origin of the switching mechanism in atomic sheets using monolayer MoS2 as a model system. Atomistic imaging and spectroscopy reveal that metal substitution into a sulfur vacancy results in a non-volatile change in the resistance, which is corroborated by computational studies of defect structures and electronic states. These findings provide an atomistic understanding of non-volatile switching and open a new direction in precision defect engineering, down to a single defect, towards achieving the smallest memristor for applications in ultra-dense memory, neuromorphic computing and radio-frequency communication systems(2,3,11).A combination of atomistic imaging and spectroscopy reveals that metal substitution into a sulfur vacancy is the underlying mechanism for resistive switching in transition metal dichalcogenide monolayers.