Influence of Physisorbed Molecules on Conductance of SWNT Networks

Speaker:

Duncan John Mowbray Postdoctoral Researcher, Center for Atomic-scale Materials Design

Co-Author(s):

Kristian Sommer Thygesen

Recent experiments have shown that the conductance of single-wall carbon nanotube (SWNT) networks is sensitive to the presence of physisorbed molecules, such as O2 and N2. However, previous calculations of the transmission function for isolated SWNTs have found physisorbed molecules have little influence on the conductance. By calculating the transmission function in the non-equilibrium Green’s function (NEGF) formalism, we show that physisorbed molecules near SWNT crossings do influence the network’s conductance. This may be understood as an increase in the tunneling probability between the SWNTs arising from overlap with the physisorbed molecule’s orbitals.