Polarimetry-based analysis of dipolar transitions of single colloidal CdSe/CdS dot-in-rods

Clotilde Lethiec (1) , F. Pisanello (2) , L. Carbone (3) , A. Bramati (4) , Laurent Coolen (1) , Agnès Maitre (1)

1 INSP - Institut des Nanosciences de Paris
2 IIT - Istituto Italiano di Tecnologia
3 Istituto di Nanoscienze- CNR
4 LKB (Jussieu) - Laboratoire Kastler Brossel

We use polarization resolved micro-photoluminescence to analyze the dipolar nature of single core/shell cadmium selenide/cadmium sulfide (CdSe/CdS) dot-in-rods. Polarization analysis, anisotropy measurements on more than 400 nanoparticles, and defocused imaging suggest that these nanoparticles behave as linear dipoles. The same methods were also used to determine the threedimensional orientation of the emission dipole, which proved to be consistent with the hypothesis of a linear dipole tilted with respect to the rod axis. Moreover, we observe that for high-energy pumping, the excitation transition of the dot-in-rod cannot be approximated by a single linear dipole, contrary to the emission transition.

Mots clés: polarimetry; fluorescence microscopy; single-photon sources; dipolar transition; colloidal nanoemitters; semiconductor core/shell nanorod

Domaines: Matière Condensée [cond-mat]

Clotilde Lethiec, F. Pisanello, L. Carbone, A. Bramati, Laurent Coolen, et al.. Polarimetry-based analysis of dipolar transitions of single colloidal CdSe/CdS dot-in-rods. New Journal of Physics, 2014, 16, pp.1-19. ⟨10.1088/1367-2630/16/9/093014⟩. ⟨hal-01236752⟩