Abstract
We report the changes in dispersion relations of hypersonic acoustic phonons in free-standing silicon membranes as thin as ∼8 nm. We observe a reduction of the phase and group velocities of the fundamental flexural mode by more than 1 order of magnitude compared to bulk values. The modification of the dispersion relation in nanostructures has important consequences for noise control in nano- and microelectromechanical systems (MEMS/NEMS) as well as opto-mechanical devices.
| Original language | English |
|---|---|
| Pages (from-to) | 3569-3573 |
| Journal | Nano Letters |
| Volume | 12 |
| Issue number | 7 |
| DOIs | |
| Publication status | Published - 2012 |
| MoE publication type | A1 Journal article-refereed |
Keywords
- Confined phonons
- dispersion relations
- inelastic light scattering
- Si membranes
- slow phonons
- ultrathin