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Micro- and nanoelectromechanical systems have numerous applications in sensing and signal transduction. Many properties benefit from reducing the system size to the nanoscale, such as increased responsivity, enhanced tunability, lower power consumption, and higher spatial density. Two-dimensional (2D) materials represent the ultimate limit of thickness, offering unprecedented new capabilities due to their natural nanoscale dimensions, high stability, high mechanical strength, and easy electronic integration. Here, we review the primary design principles, properties, applications, opportunities, and challenges of 2D materials as the building blocks of NEMS (2D NEMS) with a focus on nanomechanical resonators. First, we review the techniques used to design, fabricate, and transduce the motion of 2D NEMS. Then, we describe the dynamic behavior of 2D NEMS including vibrational eigenmodes, frequency, nonlinear behavior, and dissipation. We highlight the crucial features of 2D NEMS that enhance or expand the functionalities found in conventional NEMS, such as high tunability and rich nonlinear dynamics. Next, we overview the demonstrated applications of 2D NEMS as sensors and actuators, comparing their performance metrics to those of commercial MEMS. Finally, we provide a perspective on the future directions of 2D NEMS, such as hybrid quantum systems, integration of active 2D layers into nanomechanical devices, and low-friction interfaces in micromachines.
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Two-dimensional FePS3 nanoelectromechanical resonators with local-gate electrostatic tuning at room temperature
Nanoelectromechanical systems (NEMS) enabled by two-dimensional (2D) magnetic materials are promising candidates for exploring ultrasensitive detection and magnetostrictive phenomena, thanks to their high mechanical stiffness, high strength, and ultralow mass. The resonance modes of such vibrating membrane NEMS can be probed optically and also manipulated mechanically via electrostatically induced strain. Electrostatic frequency tuning of 2D magnetic NEMS resonators is, thus, an important means of investigating magneto-mechanical coupling mechanisms. Toward realizing magneto-mechanical coupled devices, we build circular drumhead iron phosphorus trisulfide (FePS3) NEMS resonators with different diameters (3–7 μm). Here, we report on experimental demonstration of tunable antiferromagnet FePS3 drumhead resonators with the highest fractional frequency tuning range up to Δf/f0 = 32%. Combining experimental results and analytical modeling of the resonance frequency scaling, we attain quantitative understanding of the elastic behavior of FePS3, including the transition from “membrane” to “plate” regime, with built-in tension (γ) ranging from 0.1 to 2 N/m. This study not only offers methods for investigating mechanical properties of ultrathin membranes of magnetic 2D materials but also provides important guidelines for designing future high-performance magnetic NEMS resonators.
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- Award ID(s):
- 2326528
- PAR ID:
- 10593786
- Publisher / Repository:
- American Institute of Physics
- Date Published:
- Journal Name:
- Journal of Applied Physics
- Volume:
- 136
- Issue:
- 23
- ISSN:
- 0021-8979
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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