Collisional interferometry of levitons in quantum Hall edge channels at ν=2

Abstract

We consider a Hong-Ou-Mandel interferometer for Lorentzian voltage pulses applied to Quantum Hall edge channels at filling factor $\nu=2$. Due to inter-edge interactions, the injected electronic wave-packets fractionalize before partitioning at a quantum point contact. Remarkably enough, differently from what theoretically predicted and experimentally observed by using other injection techniques, we demonstrate that, when the injection occurs through time-dependent voltage pulses (arbitrarily shaped), the Hong-Ou-Mandel noise signal always vanishes for a symmetric device, and that a mismatch in the distances between the injectors and the point of collision is needed in order to reduce the visibility of the dip. We also show that, by properly tuning these distances or by applying different voltages on the two edge channels in each arm of the interferometer, it is possible to estimate the intensity of the inter-edge interaction. The voltage pulses are chosen of the Lorentzian type because of their experimental relevance.