AI 中文总结
本文研究量子电路中库仑拖拽的磁振荡、非线性与非互易性，推导线性拖拽电导闭式表达式，分析非线性拖拽及耗散诱导非互易性，阐明各机制对拖拽振荡的影响。
AI 中文摘要
我们研究由绝热收缩结构（即量子点接触和短量子线通道）构成的相互耦合量子电路中的库仑拖拽问题。空间限域与磁场的相互作用，使得拖拽电流随栅极电压和磁场呈现出丰富的振荡响应：拖拽峰跟踪磁电子子带的退布居，在逆磁场中渐近周期性变化，其可见性由温度与收缩结构的磁场锐化隧穿宽度的竞争关系决定。我们推导了线性拖拽电导的闭式表达式，在热长度远大于线间耦合范围的实验相关极限下，其相互作用核显著简化；研究了非线性区域的拖拽效应，此时拖拽电流可测量任意磁场下驱动通道的跨导；还讨论了由耗散诱导的拖拽信号非互易性的物理动机模型。考虑塞曼分裂、势垒透射的相互作用重整化、高场下的背散射以及电路耦合的频率结构的扩展分析，阐明了各机制如何将自身特征烙印在拖拽振荡的温度依赖性和线形上。
英文摘要
We consider the problem of Coulomb drag in interactively coupled quantum circuits built of adiabatic constrictions: quantum point contacts and short quantum-wire channels. The interplay of spatial confinement and magnetic field leads to a rich oscillatory response of the drag current as a function of gate voltage and magnetic field: drag peaks track the depopulation of magnetoelectric subbands, are asymptotically periodic in inverse field, and their visibility is controlled by the competition of temperature with the field-sharpened tunneling width of the constriction. We derive a closed expression for the linear drag conductance whose interaction kernel simplifies dramatically in the experimentally relevant limit of a long thermal length compared with the range of the interwire coupling, investigate the drag in the nonlinear regime, where the drag current measures the transconductance of the drive channel at any field, and discuss physically motivated models of dissipation-induced nonreciprocity of the drag signal. Extensions accounting for Zeeman splitting, interaction renormalization of the barrier transmission, backscattering at high field, and the frequency structure of the circuit coupling delineate how each mechanism imprints itself on the temperature dependence and lineshapes of the drag oscillations.
Comments14 pages, 10 figures
