2008/03/31 by Matthias Imboden, Pritiraj Mohanty
Engineering · Physics and Astronomy · #Advanced Fiber Laser Technologies #Mechanical and Optical Resonators #Photonic and Optical Devices #cond-mat.mes-hall #cond-mat.mtrl-sci
paper · pdf · doi:10.1103/physrevb.79.125424
5 pages, two figures, one table, two-column format. Related papers can be found at http://nano.bu.edu/
arxiv created 2009/03/11 · openalex publication_date 2009/03/23 · arxiv updated 2009/12/01 · openalex created_date 2025/10/10 · openalex updated_date 2026/07/28
We report kelvin- to millikelvin-temperature measurements of dissipation and frequency shift in megahertz-range resonators fabricated from ultrananocrystalline diamond. Frequency shift \ensuremathδf/f0 and dissipation Q^\ensuremath-1 demonstrate temperature dependence in the millikelvin range similar to that predicted by the glass model of tunneling two-level systems. The logarithmic temperature dependence of \ensuremathδf/f0 is in good agreement with such models, which include phonon relaxation and phonon resonant absorption. Dissipation shows a weak power law, Q^\ensuremath-1\ensuremath∝T1/3, followed by saturation at low temperature. A comparison of both the scaled frequency shift and dissipation in equivalent micromechanical structures made of single-crystal silicon and gallium arsenide indicates universality in the dynamical response.