Quantum Transport in a Biphenyl Molecule: Effects of Magnetic Flux

Electron transport properties of a biphenyl molecule are studied based on the Green's function formalism. The molecule is sandwiched between two metallic electrodes, where each benzene ring is threaded by a magnetic flux $\phi$. The results are focused on the effects of the molecule to electrode coupling strength and the magnetic flux $\phi$. Our numerical study shows that, for a fixed molecular coupling, the current amplitude across the bridge can be {\em regulated} significantly just by tuning the flux $\phi$. This aspect may be utilized in designing nano-scale electronic circuits.