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Spin effects in transport through non-Fermi liquid quantum dots

F. Cavaliere·A. Braggio·M. Sassetti·B. Kramer
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Abstract

The current-voltage characteristic of a one dimensional quantum dot connected via tunnel barriers to interacting leads is calculated in the region of sequential tunneling. The spin of the electrons is taken into account. Non-Fermi liquid correlations implying spin-charge separation are assumed to be present in the dot and in the leads. It is found that the energetic distance of the peaks in the linear conductance shows a spin-induced parity effect at zero temperature T. The temperature dependence of the positions of the peaks depends on the non-Fermi liquid nature of the system. For non-symmetric tunnel barriers negative differential conductances are predicted, which are related to the participation in the transport of collective states in the quantum dot with larger spins. Without spin-charge separation the negative differential conductances do not occur. Taking into account spin relaxation destroys the spin-induced conductance features. The possibility of observing in experiment the predicted effects are briefly discussed.

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F. Cavaliere, A. Braggio, M. Sassetti, B. Kramer. 2004-07-07. Spin effects in transport through non-Fermi liquid quantum dots. https://doi.org/10.1103/physrevb.70.125323

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