Shot noise and thermopower in aromatic molecules

The quantum transport properties of finite homogeneous chains of aromatic molecules composed of one, two or several benzene rings connected to two semi-infinite leads are studied. We study these molecules based on the tight-binding approach. The calculation of the transport properties is performed using Greens function techniques within a real space renormalization scheme. In particular, we focus on the transmission probability, on the noise power of current fluctuations and on the thermopower. Our results show different transport regimes for these molecular systems as a function of the coupling intensities and the length of chains.