Issue |
EPL
Volume 112, Number 5, December 2015
|
|
---|---|---|
Article Number | 57001 | |
Number of page(s) | 6 | |
Section | Condensed Matter: Electronic Structure, Electrical, Magnetic and Optical Properties | |
DOI | https://doi.org/10.1209/0295-5075/112/57001 | |
Published online | 21 December 2015 |
Reappearance of the Kondo effect in serially coupled symmetric triple quantum dots
1 Department of Physics, Renmin University of China - Beijing 100872, China
2 Hefei National Laboratory for Physical Sciences at the Microscale, University of Science and Technology of China Hefei, Anhui 230026, China
3 Department of Chemistry, Hong Kong University of Science and Technology - Kowloon, Hong Kong
(a) wjh@ruc.edu.cn
Received: 22 September 2015
Accepted: 25 November 2015
We investigate the spectral properties of a serially coupled triple quantum dot (STQD) system by means of the hierarchical equations of motion (HEOM) approach. We find that with the increase of the interdot coupling t, the first Kondo screening is followed by another Kondo effect reappearing due to the transition from the respective Kondo singlet state of individual QD to the coherence bonding state generated among the three QDs. The reappearance of the Kondo effect results in the three-peak structure of the spectral functions of peripheral QD-1(3). By investigating the susceptibility χ, we find that the local susceptibility of intermediate QD-2 is a positive value at weak interdot coupling, while it changes into a negative value at strong interdot coupling, at which the STQD system gives rise to the reappearance of the Kondo effect. We also find that the slopes of will deviate from a straight line behaviour at low temperature in the reappearing Kondo regime. In addition, the influence of temperature and dot-lead coupling strength on the reappearing Kondo effect as well as the Kondo-correlated transport properties are afterwards exploited in detail.
PACS: 72.15.Qm – Scattering mechanisms and Kondo effect / 73.63.Kv – Quantum dots / 73.63.-b – Electronic transport in nanoscale materials and structures
© EPLA, 2015
Current usage metrics show cumulative count of Article Views (full-text article views including HTML views, PDF and ePub downloads, according to the available data) and Abstracts Views on Vision4Press platform.
Data correspond to usage on the plateform after 2015. The current usage metrics is available 48-96 hours after online publication and is updated daily on week days.
Initial download of the metrics may take a while.