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arXiv · 0707.4271

Many-body excitations in tunneling current spectra of a few-electron quantum dot

D. V. Melnikov·T. Fujisawa·D. G. Austing·S. Tarucha·J. -P. Leburton
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Abstract

Inherent asymmetry in the tunneling barriers of few-electron quantum dots induces intrinsically different tunneling currents for forward and reverse source-drain biases in the non-linear transport regime. Here we show that in addition to spin selection rules, overlap matrix elements between many-body states are crucial for the correct description of tunneling transmission through quantum dots at large magnetic fields. Signatures of excited (N-1)-electron states in the transport process through the N-electron system are clearly identified in the measured transconductances. Our analysis clearly confirms the validity of single-electron quantum transport theory in quantum dots.

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D. V. Melnikov, T. Fujisawa, D. G. Austing, S. Tarucha, J. -P. Leburton. 2007-07-30. Many-body excitations in tunneling current spectra of a few-electron quantum dot. https://doi.org/10.1103/physrevb.77.165340

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