VO2: A Material for High-performance Micro/Nanoactuators

Vanadium Dioxide (VO2) is an interesting material for micro/nanoactuators due to its fast and reversible Solid State Phase Transitions (SSPT) at 68° that in single crystals shows strain values up to 1 % and large applied forces. This transition is hysteretic and occurs in a temperature window of 5-10 °C. In thin films it shows percolative behavior, spreading with the switching of single domains having micrometric or nanometric size, depending on the growing conditions. We present two VO2-based microdevices exploiting the domain structure of this SSPT. A programmable mechanical resonator having mechanical memory capabilities and a mechanical oscillator excited only by a DC source are discussed. VO2-based microactuators could add unique features to the field of nanoactuators thanks to its peculiar properties and to the possibility to preserve and control the SSPT of this material down to submicrometric scale