Viterbi Faculty of Electrical Engineering, Technion
Bi-Stable Nano Electromechanical Systems Exhibiting Snap-Through Buckling Instability Based on Carbon Nanotubes
Mechanical bi-stability based on snap-through (ST) buckling is a well-known phenomenon in micro-electromechanical systems (MEMS) which serves as the underlying mechanism for many practical applications such as switches, actuators, sensors, filters, and memory elements, to name a few. Miniaturization of these systems for nano-electromechanical systems (NEMS) is thus appealing for innovative technologies by enabling higher sensitivities, but also poses a great challenge in fabrication and design. In this seminar, we report the first ever realization of a suspended carbon nanotube (CNT) based bi-stable systems exhibiting ST buckling phenomena. Both the static and dynamic responses of the system were obtained through conductance and resonance frequency measurements, respectively. For the latter, an electrostatic actuation and detection methods were chosen, utilizing the CNT as a mixer. In both measurements, non-linear effects such as jumps, hysteresis, softening and hardening were discovered. Finally, we developed a comprehensive theoretical model based on the Euler-Bernoulli beam theory to support our findings. Apart from it being the smallest bi-stable electromechanical system based on ST buckling to date, our devices could also serve as excellent sensors with ultrahigh sensitivities, reaching electrostatic tunability values beyond 100MHz/V, which are also attractive for mechanical quantum-bits.
*PhD student supervised by Prof. Yuval Yaish.