【摘 要】
：
We present a triangular triple quantum dot (TTQD) system with two dots connected parallelly to one conduction lead,and investigate the phase diagram,the electric transport,and the temperature-dependen
【机 构】
：
School of Science, Hubei University of Automotive Technology,Shiyan 442002, People's Republic of Ch
【出 处】
：
第十九届全国凝聚态理论与统计物理学术会议
论文部分内容阅读
We present a triangular triple quantum dot (TTQD) system with two dots connected parallelly to one conduction lead,and investigate the phase diagram,the electric transport,and the temperature-dependent magnetic moment at half filling.When the hopping between two connected dots t12 =0,and those between the connected dots and the side dot are symmetric t13 =t23,two connected dots form a spin triplet due to the Ruderman-Kittel-Kasuya-Yosida (RKKY) interaction mediated by the dot-lead coupling and/or the hopping t13 Fort13 =0,the triplet is partially screened by the conduction leads at low temperature.Both the connected dots and the side dot contribute to the magnetic moment of the system.For any definite t13,the triplet is totally screened by the conduction leads and the side dot,and the two-stage Kondo effect occurs.When t12 increases beyond a critical t12c,two connected dots form a spin singlet and decouple from the side dot.In this case,the Kondo peak is strongly suppressed,indicating zero conductance,and only the localized side dot contribute to the magnetic moment at low temperature.Whent13 ≠ t23,we find a crossover as t12 increases,contrast to the first order transition of the symmetric case.Numerical renormalization group technique and physical arguments are used to obtain a detailed understanding of these problems.
其他文献
用基于玻尔兹曼方程的宏观近似，我们在理论上研究了自旋阀中由于输运导致的热产生。分析结果表明，磁性多层结构中的额外热产生表现出与巨磁阻效应类似的行为。在自旋阀中，由于自旋积累导致的额外热产生与自旋耦合界面电阻的焦耳热是相等的，经证明这是一个普适的结论。但是，在单独的各层中，热产生并不满足焦耳定律。更细节的研究表明，额外热产生是由于自旋扩散过程和自旋反转散射导致，在半无限层中，两种作用的贡献相等。另一
An asymmetric periodic device driven by both a high-frequency signal and a lowffequency signal is investigated.First,the phenomenon of multiple current reversals is observed by varying amplitude of th
The nanocrystalline (Na0.7K0.3)0.5Bi0.5TiO3 plates present room temperature ferromagnetism.The reduction of ferromagnetism for the (Na0.7K0.3)0.5Bi0.5TiO3 plate with subsequent long time and high temp
A quantum spin liquid state is a Mott insulator without any long-range magnetic order down to the lowest temperature.For the typical candidate material κ-(ET)2Cu2(CN)3,which is believed to be describe
低维量子自旋系统一真是凝聚态物理的研究热点,钻石链自旋模型作为其中的成员之一在过去几年受到了广泛关注[1]。尤其是具有钻石形拓扑结构的阻挫自旋链模型材料Cu3(CO3)2(OH)2的发现,其表现出地有趣磁行为引起了人们对该体系的深入研究[2,3]。本文在前人工作基础上,构建了具有伊辛-海森堡交替键的混自旋(1/2,1)阻挫钻石链系统,考虑竖直方向为S=1的海森堡自旋并带有单离子各向异性,水平节点处
Superconductivity and superconductors have always been the most attractive topic in condensed matter physics for one century,while magnetoelectricity and multiferroics have become another emergent hot
The thermodynamic properties of the frustrated arbitrary spin-S J1-J2 Heisenberg antiferromagnet on the body-centered-cubic lattice for Néel phase are systematically calculated by use of the double-ti
Contactless acoustic control systems have recently garnered considerable attention because of its broad application prospects,such as acoustic levitations,particles manipulations,sensor and ultrasonic
The theoretical study of grain boundaries (GBs) in polycrystalline semiconductors is currently stalemated by their complicated nature, which is difficult to extract from any direct experimental charac