We identify the existence of nonlinear thermo-visco-elastic damping in conductive metallic nanowires that are subject to magnetic excitation and investigate its effects on the spatiotemporal dynamical system response. We derive a consistent continuum-based modal dynamical system for a geometrically nonlinear thermo-visco-elastic nanowire and employ a combined asymptotic and numerical methodology to estimate the magnitude of viscoelastic and thermal damping from controlled benchmark nanowire experiments. The criteria for bistable planar response estimated from experiments of nanowires documented in the literature enables estimation of both thermal and viscoelastic damping parameters for small magnetomotive excitation.
The slowly-varying evolution equations derived by the asymptotic multiple-scales method reveal coexisting periodic planar and spatial whirling solutions that lose their orbital stability via a secondary Hopf bifurcation. Numerical analysis of the dynamical system for finite excitation amplitude validates the transition from quasi-periodic to chaotic solutions. This research demonstrates the significance of non-negligible thermal and viscoelastic damping for nanowires in a high vacuum environment. Furthermore, the consistent derivation of magneto-motive excitation reveals combined external and parametric excitation that can drive the nanowire to nonstationary spatiotemporal whirling.
