Kondo Effect Versus Magnetic Coupling in Indirectly Coupled Double Quantum Dots

• Published in: Communications in theoretical physics Vol. 54; no. 11; pp. 933 - 937
• Main Author: 龙文 孙庆丰
• Format: Journal Article
• Language: English
• Published: IOP Publishing 15.11.2010
• Subjects: 成分组成; 磁场耦合; 磁耦合作用; 耦合双量子点; 重费米子系统; 铁磁相
• ISSN: 0253-6102
• DOI: 10.1088/0253-6102/54/5/28

We theoretically investigate a device consisting of two quantum dots （QDs） side-coupled to a quantum wire which has many physical ingredients of an artificial heavy fermion system. An extra parameter, the distance L between the two QDs, is introduced and it plays an important role on the competition of the Kondo temperature and magnetic coupling. Three different phases are found： antiferromagnetic phase, Kondo phase with spin S = 1/2, and Kondo phase with S = 1, depending on the distance L, the magnetic properties are qualitatively different for different phases： conductance tends to the unitary value 2e2 /h; for the S ： the distance. coupling, and the Kondo temperature. Quantum transport for the S = 1 Kondo and the antiferromagnetic phases, the 1/2 Kondo phase the conductance is strongly dependent onthe distance.