Abstract

Within the 2D theory of dissipative tunneling in the semiclassical approximation (a rarefied gas of instanton–anti-instanton pairs) at a finite temperature in the presence of an external electric field, the features of tunneling transport in the planar structures with the quantum dots made of colloidal gold—which, presumably, possess the properties of a metamaterial—are investigated. It is shown experimentally that either a single effect or a double effect of 2D tunnel bifurcations (in the form of a kink or kinks on the tunneling current–voltage curve) is observed depending on the position of the cantilever tip of a combined atomic force and scanning tunneling microscope (AFM/STM), which can be either above a single quantum dot or between two adjacent quantum dots, respectively. As our theoretical model shows, such a regime of double bifurcation (a double smoothed kink on the tunneling current–voltage curve) that is associated with the manifestation of the properties of a metamaterial by the structure under study. A convincing qualitative agreement is obtained between the experimental current–voltage characteristics and the field dependence of the probability of 2D dissipative tunneling in the two investigated regimes with due regard for the observed quantum beats (oscillations) in the vicinity of 2D bifurcation points.

中文翻译：

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金纳米颗粒阵列中耗散电子隧穿中的二维分叉特征

摘要

在二维温度下，在有限的温度下，在存在外部电场的情况下，半经典近似（耗散的瞬时子-反实例化气体）的二维耗散隧穿理论中，具有量子点的平面结构中的隧穿传输特征研究了胶体金（大概具有超材料的特性）的研究。实验表明，根据结合的原子力和原子力的悬臂尖端的位置，可以观察到二维隧道分叉的单作用或双作用（以隧道电流-电压曲线上的一个或多个扭结的形式）。扫描隧道显微镜（AFM / STM），可以分别位于单个量子点上方或两个相邻量子点之间。正如我们的理论模型所示，这种双分叉的状态（在隧道电流-电压曲线上有双平滑的扭结）与所研究结构的超材料的性能表现有关。在适当考虑了在二维分叉点附近观察到的量子拍（振荡）的情况下，在两个研究方案中，实验电流-电压特性与二维耗散隧穿概率的场相关性之间获得了令人信服的定性一致。