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arXiv · 1403.8047

Real time decoherence of Landau and Levitov quasi-particles in quantum Hall edge channels

D. Ferraro·B. Roussel·C. Cabart·E. Thibierge·G. Fève·C. Grenier·P. Degiovanni
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Abstract

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 $ν=2$. 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.

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D. Ferraro, B. Roussel, C. Cabart, E. Thibierge, G. Fève, C. Grenier, P. Degiovanni. 2014-03-31. Real time decoherence of Landau and Levitov quasi-particles in quantum Hall edge channels. https://doi.org/10.1103/physrevlett.113.166403

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