Indistinguishable single photons generated by a quantum dot under resonant excitation observable without postselection

Léonard Monniello (1) , Antoine Reigue (1) , Richard Hostein (1) , Aristide Lemaitre (2) , Anthony Martinez (2) , Roger Grousson (1) , Valia Voliotis (1)

1 INSP - Institut des Nanosciences de Paris
2 LPN - Laboratoire de photonique et de nanostructures

We report on two-photon interference of highly indistinguishable single photons emitted by a quantum dot. Strictly resonant excitation with picosecond laser pulses has been used to prepare coherent states with a significantly increased coherence time (T-2 similar to 1 ns) and reduced lifetime (T-1 similar to 650 ps), as compared to a nonresonant excitation scheme. Indistinguishable photons, with visibilities greater than 70%, have been observed by measuring the Hong-Ou-Mandel dip without postselection of the interfering photons. Near-unity indistinguishable photons should be achievable by preventing fluctuations in the electrostatic environment in the vicinity of the dots, considered as an important source of decoherence.

Domaines: Matière Condensée [cond-mat]

Léonard Monniello, Antoine Reigue, Richard Hostein, Aristide Lemaitre, Anthony Martinez, et al.. Indistinguishable single photons generated by a quantum dot under resonant excitation observable without postselection. Physical Review B: Condensed Matter and Materials Physics (1998-2015), 2014, 90 (4), pp. 041303(R). ⟨10.1103/PhysRevB.90.041303⟩. ⟨hal-01229151⟩