Electronic transport through N quantum dots under DC bias

• Published in: Physica. B, Condensed matter Vol. 308; pp. 1117 - 1120
• Main Authors: Shangguan, W.Z., Au Yeung, T.C., Yu, Y.B.
• Format: Journal Article
• Language: English
• Published: Elsevier B.V 01.12.2001
• Subjects: Equation of motion method; Nonequilibrium Green's function; Quantum dot array; Quantum transport; Equation of motion method; Quantum dot array; Quantum transport; Nonequilibrium Green's function
• ISSN: 0921-4526; 1873-2135
• DOI: 10.1016/S0921-4526(01)00902-4

This work deals with the electronic transport in a system of an arbitrary number of quantum dots connected in series by tunnel coupling. We calculate the “lesser” and retarded Green's functions based on the nonequilibrium Green's function formalism developed by Jauho et al. [Phys. Rev. B 50 (1994) 5528] for a one-dimensional N dot array, where N is an arbitrary positive integer, and we derive an analytical formula for the current under DC bias voltage. The retarded self-energy defined for any individual dot in the array is found to be made up of left and right components and to be of the staircase type, terminating at the two electron reservoirs. For simplicity of numerical computation, we take the 3-dot case for demonstration. The density of states of the 3-dot system is studied by plotting the differential conductance against the Fermi level of the left lead.