Anomalous Thermomechanical Softening-Hardening Transitions in Micro-oscillators

Keywords:
nonlinear dynamics, resonance, softening, hardening, optical detection

Abstract:
This work documents and explains a counter-intuitive nonlinear phenomenon, where the laser-detected resonant motion of forced, micromechanical oscillators can be tuned from softening to hardening by increasing the laser power incident on a prestressed silicon nitride oscillator. This tuning is explained by a thermo-mechanical model in which linear and nonlinear stiffness contributions have opposing responses to temperature change.

Nanotech 2008 Conference Program Abstract