| AVS 65th International Symposium & Exhibition | |
| MEMS and NEMS Group | Thursday Sessions |
| Session MN+2D+AN+MP+NS-ThM |
| Session: | Optomechanics and 2D NEMS |
| Presenter: | Zenghui Wang, University of Electronic Science and Technology of China |
| Authors: | Z. Wang, University of Electronic Science and Technology of China R. Yang, Case Western Reserve University P.X.-L. Feng, Case Western Reserve University |
| Correspondent: | Click to Email |
Atomic layer semiconducting crystals have emerged as a new class of two-dimensional (2D) materials, exhibiting great promises for both fundamental research and technological applications. Their outstanding electromechanical properties make these materials ideal for constructing novel 2D NEMS, providing opportunities for leveraging their unique device properties across multiple information-transduction domains, at scales down to individual atomic layers. One particularly interesting category of 2D NEMS is 2D nanoelectromechanical resonators, which hold potentials for making the next generation RF signal transduction and processing components, with miniaturized size, ultra-low power consumption, and compatibility with transparent and flexible circuits.
Towards future applications in the 5G era, multi-band RF signal handling capability is desired, as the number of bands each mobile device need to have access to significantly increases, and it would be impractical to simply increase the number of RF components that can only function under one RF frequency, as the space required for mounting such components scales with the number of bands. Therefore, ultralow-power tunable and reconfigurable RF devices that can adapt to different frequencies would be one solution to this challenge.
Here we present experimental demonstration of nanomechanical resonators based on layered MoS2 atomic crystals that have reconfigurable resonant responses. By carefully studying the temperature-dependent frequency response in such MoS2 resonators[1], we discover clear, repeatable hysteretic behavior as the device temperature is changed[2]. Leveraging this phenomenon, we achieve switchable resonance frequency fres in such devices by using heating and cooling pulses. Specifically, for an example MoS2 resonator, during heating pulses, the fres decreases to ~20MHz. Once the device recovers to room temperature, fres stabilizes at ~26MHz. During cooling pulses, fres increases to ~29MHz, and upon reverting to room temperature fres stays at ~24.5MHz, which is clearly different than the other room temperature state. Our findings suggest that such atomic-layer MoS2 NEMS resonators could be used towards developing reconfigurable RF components whose frequency response can be switched between different states.
[1] R. Yang, et al., IEEE UFFC, pp 198-201, 2015. [2] Z. Wang, et al., IEEE UFFC, pp 783-786, 2015.