Quantum phase transition and underscreened Kondo effect in electron transport through parallel double quantum dots
Abstract
We investigate electronic transport through parallel double quantum dot(DQD) system with strong on-site Coulomb interaction and capacitive interdot coupling. By applying numerical renormalization group(NRG) method, the ground state of the system and the transmission probability at zero temperature have been obtained. For a system of quantum dots with degenerate energy levels and small interdot tunnel coupling, the spin correlations between the DQDs is ferromagnetic, and the ground state of the system is a spin 1 triplet state. The linear conductance will reach the unitary limit () due to the underscreened Kondo effect at low temperature. As the interdot tunnel coupling increases, there is a quantum phase transition from ferromagnetic to anti-ferromagnetic spin correlation in DQDs and the linear conductance is strongly suppressed.
Cite
@article{arxiv.0903.2685,
title = {Quantum phase transition and underscreened Kondo effect in electron transport through parallel double quantum dots},
author = {Guo-Hui Ding and Fei Ye and Bing Dong},
journal= {arXiv preprint arXiv:0903.2685},
year = {2015}
}
Comments
5 pages, 5 figures, references added