Lee Jaesung, Wang Zenghui, He Keliang, Yang Rui, Shan Jie, Feng Philip X-L
Department of Electrical Engineering and Computer Science, Case School of Engineering, Case Western Reserve University, Cleveland, OH 44106, USA.
Institute of Fundamental and Frontier Sciences, University of Electronic Science and Technology of China, Chengdu, Sichuan 610054, China.
Sci Adv. 2018 Mar 30;4(3):eaao6653. doi: 10.1126/sciadv.aao6653. eCollection 2018 Mar.
Atomically thin semiconducting crystals [such as molybdenum disulfide (MoS)] have outstanding electrical, optical, and mechanical properties, thus making them excellent constitutive materials for innovating new two-dimensional (2D) nanoelectromechanical systems (NEMS). Although prototype structures have recently been demonstrated toward functional devices such as ultralow-power, high-frequency tunable oscillators and ultrasensitive resonant transducers, both electrical tunability and large dynamic range (DR) are critical and desirable. We report the first experimental demonstration of clearly defined single-, bi-, and trilayer MoS 2D resonant NEMS operating in the very high frequency band (up to ~120 MHz) with outstanding electrical tunability and DR. Through deterministic measurement and calibration, we discover that these 2D atomic layer devices have remarkably broad DR (up to ~70 to 110 dB), in contrast to their 1D NEMS counterparts that are expected to have limited DR. These 2D devices, therefore, open avenues for efficiently tuning and strongly coupling the electronic, mechanical, and optical properties in atomic layer semiconducting devices and systems.
原子级薄的半导体晶体[如二硫化钼（MoS）]具有出色的电学、光学和机械性能，因此使其成为创新新型二维（2D）纳米机电系统（NEMS）的优异构成材料。尽管最近已展示出用于诸如超低功耗、高频可调振荡器和超灵敏谐振换能器等功能器件的原型结构，但电可调性和大动态范围（DR）都是至关重要且令人期待的。我们报道了首个在甚高频波段（高达约120 MHz）工作的、具有出色电可调性和动态范围的明确界定的单层、双层和三层MoS二维谐振NEMS的实验演示。通过确定性测量和校准，我们发现这些二维原子层器件具有显著宽广的动态范围（高达约70至110 dB），这与其一维NEMS对应物预期具有有限动态范围形成对比。因此，这些二维器件为在原子层半导体器件和系统中有效调谐以及强耦合电子、机械和光学特性开辟了途径。
