【正文】
A NanoTuneable Pressure Switch System Design Based On Single Wall Carbon Nanotubes Yazdi and Mashadi Faculty of Mechanical Engineering,University of Tehran, Iran Abstract:Under hydrostatic pressure, the cross section of a Single Wall Carbon Nanotube(SWNT) reduces uniformly and proportionally to the applied pressure until it reaches to SWNT39。s first transition addition, SWNT kinks,bees unstable and collapses on a ground plane due to bending phenomenon is a function of SWNT diameter. Bending loads can be generated by inducing a voltage between SWNT and a conductive ground plane. Therefore ,by inducing a certain Pullin voltage relative to a certain diameter(pressure), SWNT does not collapse until the applied pressure reaches to a certain amount which causes a certain SWNT diameter this case, because of SWNT collapse on the ground plane, there will be a connection between them closing an electric this study, these characteristics are employed to introduce a tuneable pressure switch. This type of pressure switch,in parison to previous presented one, uses only one SWNT for switching, is able to sense pressure with higher resolution and has a much simpler system. Key words:Single wall carbon nanotube, pullin voltages, electrostatic bending forces, kink, phase transition, transient pressure INTRODUCTION Single Wall Carbon Nanotubes(SWNTs) has novel mechanical properties and behaviors which have attracted many considerations and studies recently. Under hydrostatic Pressure, SWNT39。s cross section is reduced uniformly and proportionally to applied pressure, until it reaches SWNT39。s first transient pressure. In this case the SWNT physical properties change and its cross section bees elliptical. This characteristics has been used in previous presented nano pressure sensors by Wu et al.(2021), When applied pressure reaches to one of the SWNT39。s transition pressure, its cross section shape changes, turning SWNT into a semiconductive pressure sensing system has the ability to sense the change of SWNT from a conductive material to a semi conductive substance for switching. Therefore, in this way, pressure sensor needs a number of SWNT39。s. However, the number of used SWNT39。s is restricted because Gao et al.(1998)bsowed when SWNT diameter exc