Fano Interference versus Kondo Effect in Strongly Correlated T-Shaped Quantum Dots Embedded in an Aharonov--Bohm Ring
CHEN Bao-Ju 1,2, CHEN Xiong-Wen 1,2, SHI Zhen-Gang 1,2, ZHU Xi-Xiang 1,2, SONG Ke-Hui 1,2, WU Shao-Quan 3
1Department of Physics and Electronic Information Science, Huaihua University, Huaihua 4180082Research Institute of Information Science, Huaihua University, Huaihua 4180083Department of Physics, Sichuan Normal University, Chengdu 610068
Fano Interference versus Kondo Effect in Strongly Correlated T-Shaped Quantum Dots Embedded in an Aharonov--Bohm Ring
1Department of Physics and Electronic Information Science, Huaihua University, Huaihua 4180082Research Institute of Information Science, Huaihua University, Huaihua 4180083Department of Physics, Sichuan Normal University, Chengdu 610068
摘要We theoretically investigate the properties of the ground state of the strongly correlated T-shaped double quantum dots embedded in an Aharonov--Bohm ring in the Kondo regime by means of the one-impurity Anderson Hamiltonian. It is found that in this system, the persistent current depends sensitively on the parity and size of the ring. With the increase of interdot coupling, the persistent current is suppressed due to the enhancing Fano interference weakening the Kondo effect. Moreover, when the spin of quantum dot embedded in the Aharonov--Bohm ring is screened, the persistent current peak is not affected by interdot coupling. Thus this model may be a new candidate for detecting Kondo screening cloud.
Abstract：We theoretically investigate the properties of the ground state of the strongly correlated T-shaped double quantum dots embedded in an Aharonov--Bohm ring in the Kondo regime by means of the one-impurity Anderson Hamiltonian. It is found that in this system, the persistent current depends sensitively on the parity and size of the ring. With the increase of interdot coupling, the persistent current is suppressed due to the enhancing Fano interference weakening the Kondo effect. Moreover, when the spin of quantum dot embedded in the Aharonov--Bohm ring is screened, the persistent current peak is not affected by interdot coupling. Thus this model may be a new candidate for detecting Kondo screening cloud.
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2007, Vol. 24 
