Effects of reservoirs on quantum transport phenomena in mesoscopic systems

Non-equilibrium quantum mechanical distribution of electrons in reservoirs is revealed and its effects on quantum tunnelling and interference are demonstrated for the first time. A new contact model using local chemical potential is proposed, and it is described here how an infinite open system can be reduced to a finite analysis region and the role of maintaining the electric potential differences between contacts is undertaken by energy dissipation due to dielectric relaxation and scattering processes in the reservoirs. Consequently, the effects of reservoirs are characterized by the bias voltage dependence of the local chemical potential, of the ohmic drop and particularly the quantum mechanical accumulation in a cathode region. This bias voltage dependence diminishes the quantum transport phenomena, and may produce transmission probability pictures very unlike the actual system. Designing a flat potential structure in the cathode region would eliminate this degradation in the quantum transport properties.