Decoherence and relaxation of single-electron excitations induced by strong effective screened Coulomb interactions in Quantum Hall edge channels are an important challenge for the applications of electron quantum optics in quantum information and quantum sensing. In this talk, I will review the problem of electronic decoherence in the integer quantum Hall system at filling fraction 2 presenting both our theoretical approach [1,2] as well as experimental results from an Hong Ou Mandel experiment [3]. I will then discuss the issue of decoherence control by examining how the choice of a material as well as sample design can be used to limit electronic decoherence [4].

Refs : [1] Phys. Rev. B 80, 241307(R) (2009) [2] Phys. Rev. Lett. 113, 166403 (2014) [3] Phys. Rev. B 94, 115311 (2016) [4] Taming electronic decoherence in 1D chiral ballistic quantum conductors, ArXiv:1804.04054