Real time decoherence of Landau and Levitov quasi-particles in quantum   Hall edge channels
  Quantum Hall edge channels at integer filling factor provide a unique test-bench to understand decoherence and relaxation of single electronic excitations in a ballistic quantum conductor. In this Letter, we obtain a full visualization of the decoherence scenario of energy (Landau) and time (Levitov) resolved single electron excitations at filling factor $\nu=2$. We show that the Landau excitation exhibits a fast relaxation followed by spin-charge separation whereas the Levitov excitation only experiences spin-charge separation. We finally suggest to use Hong-Ou-Mandel type experiments to probe specific signatures of these different scenarios. 
D. Ferraro, B. Roussel, C. Cabart, E. Thibierge, G. F\`eve, C.   Grenier, P. Degiovanni
cond-mat.mes-hall quant-ph