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arXiv 1310.0691cond-mat.mes-hall
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整数量子霍尔效应中中性模的分数电荷

Fractional charges in emergent neutral modes at the integer quantum Hall effect

Hiroyuki Inoue, Anna Grivnin, Nissim Ofek, Izhar Neder, Moty Heiblum, Vladimir Umansky, Diana Mahalu

摘要:

在低维相互作用电子系统中,电荷分裂是一种可能的激发。一个已知的例子是在分数量子霍尔效应(Fractional Hall effect,HHE)机制中的分数电荷,这是电子之间的强库仑相互作用的结果,电子的动能被强磁场淬灭。或者,整数QHE(IQHE),其中电子在朗道能级(LL)中主要表现为独立粒子,缺乏这种分馏。然而,对于填充v=2,3,.电子在共同传播的相邻手性边缘沟道中传播,从而相互作用并改变非相互作用的LL。例如,在v=2时,选择性地注入到单个非相互作用(裸)边缘沟道中的电子预期在相互作用区域中分解成“快”模式和“慢”模式;每个模式携带在两个裸沟道之间共享的部分电荷。在这里,我们报告我们的灵敏的散粒噪声测量,确认存在这样的细分在v=2。注入分区电流到一个“热”边缘通道导致低频散粒噪声在相邻的无电流的“冷”边缘通道后,它已被分区。控制热通道和冷通道的划分允许确定两个通道中的部分电荷以及通道的速度差。这种方法可以很容易地扩展到研究在二维系统的拓扑结构支配边缘通道输运的相互作用。

英文摘要:

Charge fractionalization is a possible emergent excitation in a low-dimensional system of interacting electrons. A known example is that of fractional charges in the fractional quantum Hall effect (FQHE) regime, which is a consequence of strong Coulomb interaction among the electrons whose kinetic energy is quenched by the strong magnetic field. Alternatively, the integer QHE (IQHE), with electrons behaving largely as independent particles in Landau levels (LLs), lacks such fractionalization. However, for integer LLs filling v=2, 3,... electrons propagate in copropagating adjacent chiral edge channels, and thus interact and modify the non-interacting LLs. For example, at v=2, an electron injected selectively into a single non-interacting (bare) edge channel is expected to decompose into a 'fast' mode and a 'slow' mode in the region of interaction; each mode carry fractional charges shared between the two bare channels. Here, we report our sensitive shot noise measurement that affirms the presence of such fractionalization in v=2. Injecting partitioned current into a 'hot' edge channel led to low frequency shot noise in the adjacent currentless 'cold' edge channel after it had been partitioned. Controlling the partitioning of the hot and cold channels allowed a determination of the fractional charges in both channels as well as the channels' velocity difference. This approach can be easily extended to study interaction in two-dimensional systems with a topology dictating edge channels transport.

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。

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