Krähenmann T, Fischer S G, Röösli M, Ihn T, Reichl C, Wegscheider W, Ensslin K, Gefen Y, Meir Yigal
Solid State Physics Laboratory, ETH Zürich, CH-8093, Zürich, Switzerland.
QuTech and Kavli Institute of Nanoscience, Delft University of Technology, Delft, 2628CJ, the Netherlands.
Nat Commun. 2019 Sep 2;10(1):3915. doi: 10.1038/s41467-019-11888-1.
Quantum Hall edge channels offer an efficient and controllable platform to study quantum transport in one dimension. Such channels are a prospective tool for the efficient transfer of quantum information at the nanoscale, and play a vital role in exposing intriguing physics. Electric current along the edge carries energy and heat leading to inelastic scattering, which may impede coherent transport. Several experiments attempting to probe the concomitant energy redistribution along the edge reported energy loss via unknown mechanisms of inelastic scattering. Here we employ quantum dots to inject and extract electrons at specific energies, to spectrally analyse inelastic scattering inside quantum Hall edge channels. We show that the missing energy puzzle could be untangled by incorporating non-local Auger-like processes, in which energy is redistributed between spatially separate parts of the sample. Our theoretical analysis, accounting for the experimental results, challenges common-wisdom analyses which ignore such non-local decay channels.
量子霍尔边缘通道为研究一维量子输运提供了一个高效且可控的平台。这类通道是在纳米尺度上高效传输量子信息的一种有前景的工具，并且在揭示有趣的物理现象方面发挥着至关重要的作用。沿边缘的电流携带能量和热量，会导致非弹性散射，这可能会阻碍相干输运。几个试图探测沿边缘伴随的能量重新分布的实验报告了通过未知的非弹性散射机制导致的能量损失。在这里，我们利用量子点在特定能量下注入和提取电子，以对量子霍尔边缘通道内的非弹性散射进行光谱分析。我们表明，通过纳入非局部类俄歇过程可以解开缺失能量之谜，在这种过程中能量在样品空间上分离的部分之间重新分布。我们基于实验结果的理论分析对忽略此类非局部衰变通道的常识性分析提出了挑战。
