Professor Huang studies the deformation and fracture of solids at the microscale, typically from micron to nanometer scales. He is currently studying the coupling between mechanical deformation and electrical property of carbon nanotubes. Carbon nanotubes exhibit superior electrical properties. Metallic nanotubes can carry extremely large current to serve as interconnects in nanoelectronics. Semiconducting nanotubes can be electrically switched on and off as field-effect transistors that are more than 500 times smaller than current devices. However, recent experiments show that electrical conductance of carbon nanotubes changes by two orders of magnitude upon mechanical deformation, that is, metallic nanotubes become semiconducting ones after deformation. This unique electromechanical characteristic of carbon nanotubes has major implications for the reliability of nanotube-based electronics, because a significant electrical-property-change deformation produced in manufacture and operation processes may lead to device-malfunction.
Professor Huang is developing a nanoscale continuum theory to incorporate atomistic models directly into the continuum framework in order to determine the atomic positions of deformed carbon nanotubes. Together with tight binding calculations, his approach provides an effective way to calculate the band gap, which indicates whether a metallic carbon nanotube becomes a semiconducting one upon mechanical deformation.