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Negative differential resistance due to the resonance coupling of a quantum-dot dimer

S. D. Wang·Z. Z. Sun·N. Cue·X. R. Wang
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Abstract

Electron tunneling through a coupled quantum-dot dimer under a dc-bias is investigated. We find that a peak in the $I$-$V$ curve appears at low temperature when two discrete electronic states in the two quantum dots are aligned with each other -- resonance coupling. This leads to a negative differential resistance. The peak height and width depend on the dot-dot coupling. At high temperature, the peak disappears due to thermal smearing effects.

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S. D. Wang, Z. Z. Sun, N. Cue, X. R. Wang. 2003-05-01. Negative differential resistance due to the resonance coupling of a quantum-dot dimer. https://arxiv.org/abs/cond-mat/0305018

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