The Effect of Viscous Air Damping on an Optically Actuated Multilayer MoS₂ Nanomechanical Resonator Using Fabry-Perot Interference.
We demonstrated a multilayer molybdenum disulfide (MoS₂) nanomechanical resonator by using optical Fabry-Perot (F-P) interferometric excitation and detection. The thin circular MoS₂ nanomembrane with an approximate 8-nm thickness was transferred onto the endface of a ferrule with an inner diameter of 125 μm, which created a low finesse F-P interferometer with a cavity length of 39.92 μm. The effects of temperature and viscous air damping on resonance behavior of the resonator were investigated in the range of -10-80 °C. Along with the optomechanical behavior of the resonator in air, the measured resonance frequencies ranged from 36 kHz to 73 kHz with an extremely low inflection point at 20 °C, which conformed reasonably to those solved by previously obtained thermal expansion coefficients of MoS₂. Further, a maximum quality (Q) factor of 1.35 for the resonator was observed at 0 °C due to viscous dissipation, in relation to the lower Knudsen number of 0.0025~0.0034 in the tested temperature range. Moreover, measurements ofQfactor revealed little dependence ofQon resonance frequency and temperature. These measurements shed light on the mechanisms behind viscous air damping in MoS₂, graphene, and other 2D resonators.
School of Instrumentation Science and Opto-electronics Engineering, Beihang University, Beijing 100191, China. sheymbh@163.com.|Science and Technology on Metrology and Calibration Laboratory, Beijing 100095, China. sheymbh@163.com.
Yumei
Y
She
School of Instrumentation Science and Opto-electronics Engineering, Beihang University, Beijing 100191, China. licheng@buaa.edu.cn.|Science and Technology on Metrology and Calibration Laboratory, Beijing 100095, China. licheng@buaa.edu.cn.
Cheng
C
Li
School of Instrumentation Science and Opto-electronics Engineering, Beihang University, Beijing 100191, China. lantian435@163.com.|Science and Technology on Metrology and Calibration Laboratory, Beijing 100095, China. lantian435@163.com.
Tian
T
Lan
School of Instrumentation Science and Opto-electronics Engineering, Beihang University, Beijing 100191, China. 12171038@buaa.edu.cn.|Science and Technology on Metrology and Calibration Laboratory, Beijing 100095, China. 12171038@buaa.edu.cn.
Xiaobin
X
Peng
School of Instrumentation Science and Opto-electronics Engineering, Beihang University, Beijing 100191, China. liuqianwenok@163.com.|Science and Technology on Metrology and Calibration Laboratory, Beijing 100095, China. liuqianwenok@163.com.
Qianwen
Q
Liu
School of Instrumentation Science and Opto-electronics Engineering, Beihang University, Beijing 100191, China. shangcfan@buaa.edu.cn.|Science and Technology on Metrology and Calibration Laboratory, Beijing 100095, China. shangcfan@buaa.edu.cn.
Shangchun
S
Fan
Fabry-Perot interference; multilayer MoS2 diaphragm; resonator; viscous air damping