The ultimate limit to the emission linewidth of single nanocrystals

Mark J. Fernée (1) , Chiara Sinito (1) , Yann Louyer (2) , Philippe Tamarat (1) , Brahim Lounis (1)

1 lp2n-01,lp2n-12
2 LOMA - Laboratoire Ondes et Matière d'Aquitaine

Measurements of the emission linewidth of single nanocrystals are usually limited by spectral diffusion. At cryogenic temperatures, the origin of this instability was revealed to be photo-induced, suggesting that the spectral peak position may be stable in the limit of vanishing optical excitation. Here we test this stability using resonant photoluminescence excitation and find there is persistent spectral broadening, which ultimately limits the emission linewidth in these materials. The spectral broadening is shown to be consistent with spontaneous fluctuations of the local electrostatic field within the disordered environment surrounding the nanocrystal.

Keywords: single molecule spectroscopy- spectral diffusion; band edge exciton; semiconductor nanocrystals

Domains: Atomic and Molecular Clusters [physics.atm-clus]

Mark J. Fernée, Chiara Sinito, Yann Louyer, Philippe Tamarat, Brahim Lounis. The ultimate limit to the emission linewidth of single nanocrystals. Nanotechnology, 2013, 24, pp.465703 (1-5). ⟨10.1088/0957-4484/24/46/465703⟩. ⟨hal-00877709⟩