Conductance of atomic chains with electron-electron interaction: The embedding method

J.-L. Pichard, R. A. Molina, P. Schmitteckert, D. Weinmann, R. A. Jalabert und G.-L. Ingold

in: Quantum Information and Decoherence in Nanosystems, hrsg. von C. Glattli, M. Sanquer und J. Trần Thanh Vân, S. 327–331 (Thế Giới, 2004)

We review a new method, the embedding method, for calculating the residual conductance of an interacting nanosystem. Using DMRG techniques, we show that a nanosystem with interacting spinless fermions embedded into a non-interacting auxiliary lead behaves as a non-interacting scatterer, but with an interaction dependent elastic transmission coefficient. The method, which requires to take the limit of infinite lead length, allows to calculate the conductance of atomic chains as a function of the number of atoms and the strength of the electron-electron interaction. The results depend on the nature (smooth or abrupt) of the two contacts between the system and the lead and on the carrier density. Length-dependent oscillations of the conductance, whose period depends on the electron density in the atomic chain, can result from electron-electron scattering.