This thesis presents a set of experiments that study the interplay between the wave-particle duality of electrons and the interaction effects in systems of reduced dimensions. Both dc transport and measurements of current noise have been employed in the studies; in particular, techniques for efficiently measuring current noise have been developed specifically for these experiments.;The first four experiments study current noise auto- and cross correlations in various mesoscopic devices, including quantum point contacts, single and double quantum dots, and graphene devices.;In quantum point contacts, shot noise at zero magnetic field exhibits an asymmetry related to the 0.7 structure in conductance. The asymmetry in noise evolves smoothly into the symmetric signature of spin-resolved electron transmission at high field. Comparison to a phenomenological model with density-dependent level splitting yields good quantitative agreement. Additionally, a device-specific contribution to the finite-bias noise, particularly visible on conductance plateaus where shot noise vanishes, agrees with a model of bias-dependent electron heating.;In a three-lead single quantum dot and a capacitively coupled double quantum dot, sign reversal of noise cross correlations have been observed in the Coulomb blockade regime, and found to be tunable by gate voltages and source-drain bias. In the limit of weak output tunneling, cross correlations in the three-lead dot are found to be proportional to the two-lead noise in excess of the Poissonian value. These results can be reproduced with master equation calculations that include multi-level transport in the single dot, and inter-dot charging energy in the double dot.;Shot noise measurements in single-layer graphene devices reveal a Fano factor independent of carrier type and density, device geometry, and the presence of a p-n junction. This result contrasts with theory for ballistic graphene sheets and junctions, suggesting that the transport is disorder dominated.;The next two experiments study magnetoresistance oscillations in electronic Fabry-Perot interferometers in the integer quantum Hall regime. Two types of resistance oscillations, as a function of perpendicular magnetic field and gate voltages, in two interferometers of different sizes can be distinguished by three experimental signatures. The oscillations observed in the small (2.0 mum2) device are understood to arise from Coulomb blockade, and those observed in the big (18 mum2) device from Aharonov-Bohm interference. Nonlinear transport in the big device reveals a checkerboard-like pattern of conductance oscillations as a function of dc bias and magnetic field. Edge-state velocities extracted from the checkerboard data are compared to model calculations and found to be consistent with a crossover from skipping orbits at low fields to E&ar; x B&ar; drift at high fields. Suppression of visibility as a function of bias and magnetic field is accounted for by including energy- and field-dependent dephasing of edge electrons.
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机译：本文提出了一组实验，研究了电子的波粒二象性与降维系统中的相互作用之间的相互作用。研究中已经采用了直流传输和电流噪声测量。特别是针对这些实验，已经开发出了有效测量电流噪声的技术。前四个实验研究了各种介观器件中的电流噪声自相关和互相关，这些介观器件包括量子点触点，单量子点和双量子点以及石墨烯器件。 ；在量子点接触中，零磁场下的散粒噪声表现出与电导0.7结构有关的不对称性。噪声中的不对称平稳地演变为自旋分辨电子在高场传输的对称特征。与具有密度依赖性水平分裂的现象学模型进行比较可得出良好的定量一致性。此外，器件对有限偏置噪声的贡献（特别是在散粒噪声消失的电导高原上特别明显）与偏置依赖的电子加热模型相符;在三引线单量子点和电容耦合双量子中点，在库仑阻塞机制中观察到噪声互相关的符号反转，并且发现可通过栅极电压和源极-漏极偏置来调节。在弱输出隧穿的极限中，发现三引线点中的互相关与超过泊松值的两引线噪声成比例。这些结果可以通过主方程计算得到，其中包括单点中的多级传输和双点中的点间充电能量。;单层石墨烯器件中的热噪声测量显示了与载流子类型无关的Fano因子;密度，器件几何形状以及pn结的存在。该结果与弹道石墨烯片和结的理论形成对比，表明该传输是无序控制的。接下来的两个实验研究了在整数量子霍尔机制下电子Fabry-Perot干涉仪中的磁阻振荡。在两个大小不同的干涉仪中，两种电阻振荡（作为垂直磁场和栅极电压的函数）可以通过三个实验信号来区分。小型（2.0 mum2）器件中观察到的振荡被认为是由于库仑阻塞引起的，而大型（18 mum2）器件中所观察到的振荡是由于Aharonov-Bohm干扰引起的。大型设备中的非线性传输揭示了电导振荡的棋盘状图案，它是直流偏置和磁场的函数。从棋盘数据中提取的边缘状态速度与模型计算进行比较，发现与从低场跳过轨道到E＆ar的交叉点一致。 x B＆ar;在高地上漂流。通过包括边缘电子的依赖于能量和场的相移来解决作为偏压和磁场的函数的可见性的抑制。
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