The zero-temperature equilibrium conductance of mesoscopic devices due to single-particle resonant tunneling was first described by Landauer [1]. The Landauer formula was later extended to the multi-channel case by Fisher and Lee [2], who reduced the problem of calculating electronic transport properties to the problem of solving for the Green's function for a given system geometry. / In this work, the single-particle formalism is extended to the study of higher-order two-particle cotunneling processes by considering many-body Green's functions. The effect of attaching leads to the system is described in terms of a two-particle self-energy, whose analytical form is written in terms of a Feynman path integral over all possible tunneling processes between the leads and the device. In addition, an efficient numerical technique for the calculation of the fully dressed Green's function of a device region attached to two-particle leads is presented. / The problem of two-particle transport is then approached, and an analogy to single-particle transport on the infinite plane is drawn. It is shown that, for nonspin flip cotunneling processes, the two-particle transport result can be related to the single-particle conductance by way of a simple convolution. Finally, results for the cotunneling contribution to the conductance of double quantum dots, or charge qubits, are presented.
| Identifer | oai:union.ndltd.org:LACETR/oai:collectionscanada.gc.ca:QMM.101692 |
| Date | January 2006 |
| Creators | Young, Carolyn, 1979- |
| Publisher | McGill University |
| Source Sets | Library and Archives Canada ETDs Repository / Centre d'archives des thèses électroniques de Bibliothèque et Archives Canada |
| Language | English |
| Detected Language | English |
| Type | Electronic Thesis or Dissertation |
| Format | application/pdf |
| Coverage | Master of Science (Department of Physics.) |
| Rights | © Carolyn Young, 2006 |
| Relation | alephsysno: 002591237, proquestno: AAIMR32805, Theses scanned by UMI/ProQuest. |
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