Aix Marseille Université, CNRS, CPT, UMR 7332, 13288 Marseille, France and Université de Toulon, CNRS, CPT, UMR 7332, 83957 La Garde, France.
Phys Rev Lett. 2014 Jan 31;112(4):046802. doi: 10.1103/PhysRevLett.112.046802. Epub 2014 Jan 27.
We consider an electronic analog of the Hong-Ou-Mandel (HOM) interferometer, where two single electrons travel along opposite chiral edge states and collide at a quantum point contact. Studying the current noise, we show that because of interactions between copropagating edge states, the degree of indistinguishability between the two electron wave packets is dramatically reduced, leading to reduced contrast for the HOM signal. This decoherence phenomenon strongly depends on the energy resolution of the packets. Insofar as interactions cause charge fractionalization, we show that charge and neutral modes interfere with each other, leading to satellite dips or peaks in the current noise. Our calculations explain recent experimental results [E. Bocquillon Science 339 1054 (2013)] where an electronic HOM signal with reduced contrast was observed.
我们考虑了一种电子模拟的 Hong-Ou-Mandel（HOM）干涉仪，其中两个单电子沿着相反的手性边缘态传播，并在量子点接触处发生碰撞。通过研究电流噪声，我们表明由于共传播边缘态之间的相互作用，两个电子波包之间的不可分辨程度大大降低，导致 HOM 信号的对比度降低。这种退相干现象强烈依赖于波包的能量分辨率。由于相互作用导致电荷分数化，我们表明电荷和中性模式会相互干扰，导致电流噪声中出现卫星凹陷或峰值。我们的计算解释了最近的实验结果[E. Bocquillon Science 339 1054 (2013)]，其中观察到对比度降低的电子 HOM 信号。
