Effect of flux-dependent Friedel oscillations upon the effective transmission of an interacting nano-system

摘要

We consider a nano-system connected to measurement probes via non interacting leads. When the electrons interact inside the nano-system, the coefficient |t(s)(E-F)|(2) describing its effective transmission at the Fermi energy E-F ceases to be local. This effect of electron-electron interactions upon |t(s)(E-F)|(2) is studied using a one dimensional model of spinless fermions and the Hartree-Fock approximation. The non locality of |t(s)(E-F)|(2) is due to the coupling between the Hartree and Fock corrections inside the nano-system and the scatterers outside the nano-system via long range Friedel oscillations. Using this phenomenon, one can vary |t(s)(E-F)|(2) by an Aharonov-Bohm flux threading a ring which is attached to one lead at a distance L-c from the nano-system. For small distances L-c, the variation of the quantum conductance induced by this non local effect can exceed 0.1 (e(2)/h).