Determination of effective mechanical properties of a double-layer beam   by means of a nano-electromechanical transducer
  We investigate the mechanical properties of a doubly-clamped, double-layer nanobeam embedded into an electromechanical system. The nanobeam consists of a highly pre-stressed silicon nitride and a superconducting niobium layer. By measuring the mechanical displacement spectral density both in the linear and the nonlinear Duffing regime, we determine the pre-stress and the effective Young's modulus of the nanobeam. An analytical double-layer model quantitatively corroborates the measured values. This suggests that this model can be used to design mechanical multilayer systems for electro- and optomechanical devices, including materials controllable by external parameters such as piezoelectric, magnetrostrictive, or in more general multiferroic materials. 
Fredrik Hocke, Matthias Pernpeintner, Xiaoqing Zhou, Albert   Schliesser, Tobias J. Kippenberg, Hans Huebl, Rudolf Gross
cond-mat.mes-hall