arXivDaily arXiv每日学术速递 周一至周五更新
arXiv 0712.2797cond-mat.mes-hall
收藏

一维弱电子-电子相互作用导线中的电荷泵和噪声

Charge pumping and noise in a one-dimensional wire with weak electron-electron interactions

Pierre Devillard, Vladimir Gasparian, Thierry Martin

摘要:

本文研究了在电子-电子相互作用下,介观一维金属丝中电荷的绝热抽运。一个两个三角洲潜在的模型被用来描述线,它允许获得准确的散射矩阵系数,这是重整化的相互作用。在导线的两个位置施加两个周期性驱动,一个从另一个偏移,以便在没有偏置的情况下驱动电流通过导线。解析表达式的泵浦电荷,电流噪声,和Fano因子在不同的制度。这允许探索泵浦强度的整个参数范围的泵浦。我们表明,工作接近共振是必要的,有一个舒适的窗口的泵浦幅度的电荷量子化接近最佳值:一个单一的电子电荷转移在一个周期。相互作用可以改善这种情况,电荷$Q$更接近于一个电子电荷,并且噪声降低,遵循$Q (1-Q)$行为,使人联想到通过$T (1-T)$降低量子线中的噪声,其中$T$是能量传输系数。对于大的泵浦振幅,该电荷消失,噪声也减小,但比电荷慢。

英文摘要:

We consider the adiabatic pumping of charge through a mesoscopic one dimensional wire in the presence of electron-electron interactions. A two-delta potential model is used to describe the wire, which allows to obtain exactly the scattering matrix coefficients, which are renormalized by the interactions. Two periodic drives, shifted one from another, are applied at two locations of the wire in order to drive a current through it in the absence of bias. Analytical expressions are obtained for the pumped charge, current noise, and Fano factor in different regimes. This allows to explore pumping for the whole parameter range of pumping strengths. We show that, working close to a resonance is necessary to have a comfortable window of pumping amplitudes where charge quantization is close to the optimum value: a single electron charge is transferred in one cycle. Interactions can improve the situation, the charge $Q$ is closer to one electron charge and noise is reduced, following a $Q (1-Q)$ behavior, reminiscent of the reduction of noise in quantum wires by $T (1-T)$, where $T$ is the energy transmission coefficient. For large pumping amplitudes, this charge vanishes, noise also decreases but slower than the charge.

机构、总结、中文摘要均由AI分析而来,可能存在错误,请以论文正文为准。

↑