Theoretical Study of Oligophenyl-based Double Barrier Molecular Device

We report an investigation of electron conduction in oligophenyl based double barrier molecular device. We have carried out analytical calculations and numerical simulations on isolated molecules, consisting of aromatic "pi" conjugated system made up of three phenyl rings separated by insulator groups -CH_{2}-, -SiH_{2}-, -GeH_{2}- and -SnH_{2}-. We show analytically as well as numerically that when the two insulator groups are different an asymmetric electron transport in the presence of external electric field is possible,thus resembling a diode which allows one way electron transport.