振动模式对纳米器件量子输运的影响
Influence of vibrational modes on the quantum transport through a nano-device
摘要：
我们利用最近提出的散射态数值重整化群方法计算了$I(V)$和耦合到局域分子声子的单个分子能级的微分电导。我们还讨论了该模型的平衡物理，并证明了低能哈密顿量是由一个有效的相互作用共振能级模型给出的。从NRG水平流，我们直接提取有效的电荷转移规模$Γ_{\rm eff}$和动态诱导的电容耦合$U_{\rm eff}$之间的分子水平和铅电子原来是成比例的极化能移$E_p$的制度在这里调查。不同的参数制度的平衡谱函数进行了讨论。在声子频率$\w_0$的倍数处的附加声子峰对应于微分电导中的附加最大值。然而，非平衡效应导致对称结和隧道结之间的显著偏差。随着电子-声子耦合的增加，Franck-Condon封锁的标志，不对称结的电流的抑制进行了讨论与一个简单的框架相结合的（i）极化能级位移和（ii）的有效电荷转移规模$Γ_{\rm eff}$。
英文摘要：
We use the recently proposed scattering states numerical renormalization group (SNRG) approach to calculate $I(V)$ and the differential conductance through a single molecular level coupled to a local molecular phonon. We also discuss the equilibrium physics of the model and demonstrate that the low-energy Hamiltonian is given by an effective interacting resonant level model. From the NRG level flow, we directly extract the effective charge transfer scale $Γ_{\rm eff}$ and the dynamically induced capacitive coupling $U_{\rm eff}$ between the molecular level and the lead electrons which turns out to be proportional to the polaronic energy shift $E_p$ for the regimes investigated here. The equilibrium spectral functions for the different parameter regimes are discussed. The additional phonon peaks at multiples of the phonon frequency $\w_0$ correspond to additional maxima in the differential conductance. Non-equilibrium effects, however, lead to significant deviations between a symmetric junction and a junction in the tunnel regime. The suppression of the current for asymmetric junctions with increasing electron-phonon coupling, the hallmark of the Franck-Condon blockade, is discussed with a simple framework of a combination of (i) polaronic level shifts and (ii) the effective charge transfer scale $Γ_{\rm eff}$.
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。
