Dissertation Title: Highly Tunable Two-Dimensional Semiconductor Nanoelectromechanical Resonators
Date: 2024/05/15
Dissertation Title: Highly Tunable Two-Dimensional Semiconductor Nanoelectromechanical Resonators
Speaker: Pengcheng Zhang
Time: 15:30, May 15, 2024(Beijing Time)
Location: 414B, Longbin Building
Abstract
Two-dimensional (2D) materials are promising for atomic-scale, ultralow-power, and highly-tunable resonant nanoelectromechanical systems (NEMS) in sensing, communications, and computing. In pursuit of these applications, achieving a high quality (Q) factor and a broad and controllable linear DR are highly desirable, but they have not been fully explored. In this dissertation, the author first demonstrates that by tuning static strain and vibration-induced strain in suspended molybdenum disulfide (MoS2) using gate voltage, the Q factor in linear and nonlinear 2D MoS2 NEMS resonators can be effectively tuned. Furthermore, based on the gate-tunable properties, the author develops a comprehensive strain-enhanced DR model for 2D NEMS resonators, which is experimentally verified through the tuning of DRs in 2D MoS2 NEMS resonators using gate-induced strain. Finally, by leveraging the gate-tunable device characteristics, the author further develops a novel nanomechanical memory based on nonlinear 2D MoS2 NEMS resonators. This dissertation provides a promising pathway for accurately predicting and optimizing the device characteristics in NEMS resonators, towards enhanced sensitivity and SNR in mass sensing, radio-frequency signal processing, memory, and computing applications.
Biography
Pengcheng Zhang received the B.S. degree in Electronic Science and Technology from Sichuan University in 2019. He is currently a Ph.D. candidate at the UM-SJTU Joint Institute, supervised by Prof. Rui Yang. His current research interests include fundamental research in 2D NEMS resonators.