Temperature-dependent mechanical-resonance frequencies and damping in ensembles of gallium nitride nanowires
Abstract
We have measured singly clamped cantilever mechanical-resonances in ensembles of as-grown gallium nitride nanowires (GaN NWs), from 12 K to 320 K. Resonance frequencies are approximately linearly dependent on temperature near 300 K with relative shifts of 40 ± 20 ppm/K, consistent with temperature-dependent elastic moduli. Below 100 K, we find that some GaN NWs have mechanical quality factors well above 400 000, at mechanical resonance frequencies near 1 MHz. We also observe a correlation between increased amplitude of dissipation and increased temperature dependence of resonance frequencies. The microwave homodyne detection technique we use is simple, allows for the investigation of as-grown or processed NWs, and is sensitive enough to observe the thermal motion of individual NWs while providing for the simultaneous measurement of large ensembles of NW mechanical resonances.
Document Details
- Document Type
- Pub Defense Publication
- Publication Date
- Oct 22, 2012
- Source ID
- 10.1063/1.4761946
Entities
People
- C. T. Rogers
- J. R. Montague
- K. A. Bertness
- N. A. Sanford
- V. M. Bright
Organizations
- Defense Advanced Research Projects Agency
- National Institute of Standards and Technology
- National Science Foundation
- University of Colorado