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Tunneling current spectroscopy of a nanostructure junction involving multiple energy levels

David M. -T. Kuo·Yia-Chung Chang
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Abstract

A multi-level Anderson model is employed to simulate the system of a nanostructure tunnel junction with any number of one-particle energy levels. The tunneling current, including both shell-tunneling and shell-filling cases, is theoretically investigated via the nonequilibrium Green's function method. We obtain a closed form for the spectral function, which is used to analyze the complicated tunneling current spectra of a quantum dot or molecule embedded in a double-barrier junction. We also show that negative differential conductance can be observed in a quantum dot tunnel junction when the Coulomb interactions with neighboring quantum dots are taken into account.

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David M. -T. Kuo, Yia-Chung Chang. 2007-02-05. Tunneling current spectroscopy of a nanostructure junction involving multiple energy levels. https://doi.org/10.1103/physrevlett.99.086803

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