Two-stage Kondo effect in a four-electron artificial atom
摘要
An artificial atom with four electrons is driven through a singlet-triplet transition by varying the confining potential. In the triplet, a Kondo peak with a narrow dip at drain-source voltage V_ds=0 is observed. The low energy scale V_ds* characterizing the dip is consistent with predictions for the two-stage Kondo effect. The phenomenon is studied as a function of temperature T and magnetic field B, parallel to the two-dimensional electron gas. The low energy scales T* and B* are extracted from the behavior of the zero-bias conductance and are compared to the low energy scale V_ds* obtained from the differential conductance. Good agreement is found between kT* and |g|muB*, but eV_ds* is larger, perhaps because of nonequilibrium effects.
引用
@article{arxiv.cond-mat/0505359,
title = {Two-stage Kondo effect in a four-electron artificial atom},
author = {G. Granger and M. A. Kastner and Iuliana Radu and M. P. Hanson and A. C. Gossard},
journal= {arXiv preprint arXiv:cond-mat/0505359},
year = {2009}
}
备注
7 pages, 7 figures. Added labels on Fig. 3f and one reference