Kondo Effect Versus Magnetic Coupling in Indirectly Coupled Double Quantum Dots

• 来源期刊: 理论物理通讯(英文版)
• 学科: 物理学
• 关键词: 耦合双量子点 磁耦合作用 间接 重费米子系统 成分组成 磁场耦合 铁磁相 距离
• 年，卷（期）: 2010,（11）
• 所属期刊栏目: Condensed Matter： Electronic Structure, Electrical
• 页码范围: 933-937
• 页数: 5页
• 分类号: O471 O482.54
• 语种: 英文

摘要

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