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Updated: Jun 4, 2026
07:51
Fabrication of Silica Ultra High Quality Factor Microresonators
Published on: July 2, 2012
High, size-dependent quality factor in an array of graphene mechanical resonators
Robert A Barton1, B Ilic, Arend M van der Zande
1School of Applied and Engineering Physics, Kavli Institute at Cornell for Nanoscale Science, Cornell University , Ithaca, New York 14853, United States. hgc1@cornell.edu
Nano Letters
|February 8, 2011
Summary
Researchers improved the quality factor of graphene mechanical resonators by increasing their size. This breakthrough enhances graphene
Area of Science:
- Materials Science
- Nanotechnology
- Mechanical Engineering
Background:
- Graphene possesses exceptional mechanical properties, making it suitable for nanomechanical resonators.
- A key limitation for graphene resonators is their low quality factor (Q).
- Overcoming this limitation is crucial for advancing resonator performance.
Purpose of the Study:
- To investigate the effect of size on the quality factor of graphene mechanical resonators.
- To fabricate and characterize circular graphene resonators using chemical vapor deposition (CVD) graphene.
- To identify methods for enhancing the quality factor of graphene resonators.
Main Methods:
- Fabrication of circular graphene mechanical resonators of varying diameters via a simple procedure.
- Characterization of resonance frequencies, mode shapes, and quality factors.
- Systematic measurement of quality factor as a function of resonator size and modal frequency.
Main Results:
- Highly reproducible resonance frequencies and mode shapes were observed.
- A significant improvement in membrane quality factor was achieved with increasing resonator size.
- Quality factors as high as 2400 ± 300 were recorded for 22.5 μm resonators at room temperature, an order of magnitude higher than previously reported.
- Quality factor showed minimal dependence on modal frequency.
Conclusions:
- The quality factor of monolayer graphene resonators can be substantially improved by increasing their size.
- The observed Q factors suggest that graphene resonators, relative to their thickness, exhibit one of the highest quality factors among mechanical resonators.
- These findings provide insights into dissipation mechanisms in graphene resonators and highlight their potential for high-performance applications.
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