Negative differential conductance effect of the parallel coupled Quantum Dots

Autor: Jia-hao Wang, 王嘉豪
Rok vydání: 2008
Druh dokumentu: 學位論文 ; thesis
Popis: 96
Tunneling current of single-electron transistor is systematically investigated by using the Keldysh Green function method in this thesis. For one energy level case, the Coulomb staircase and Coulomb oscillation of tunneling current with respect to the applied bias and gate voltage arise from intralevel electron Coulomb interaction. We also found that tunneling rate ratio significantly influences the tunneling current spectrum. For two energy level case, the interlevel Coulomb interactions as well as intralevel Coulomb interactions exist remarkable effect on the tunneling current. Finally, we study the tunneling current through paralleled two quantum dot system. The tunneling current shows the negative differential conductance (NDC) behavior resulting from the interdot Coulomb interactions. Such a NDC effect exists in the quantum dot with shell-filling condition.
Databáze: Networked Digital Library of Theses & Dissertations