Abstract
This thesis focus on both the biexciton's stability in carbon nanotubes, and the control of the nanotube emission through its coupling to plasmonic antenna.We report the first observation of biexciton in carbon nanotubes by means of spectral holeburning nonlinear optical spectroscopy. More precisely, two induced absorption lines are detected and assigned to trion and biexciton after investigation of their temperature and pump power dependences. An additional proof of the detection of the biexciton, as an elementary excitation of carbonnanotubes, is given in a three-beam configuration based on a two-pump scheme. The biexciton of the (9,7) chirality is observed with a binding energy of 107 ± 1 meV and shows an asymetric Fano lineshape. A first estimation of the biexciton's recombinaison dynamics is given by the quantitative analysis of the nonlinear signal. Our analytic model is formulated in the framework of the chi(3) nonlinear response, including coulomb interaction between biexcitons and free electron-hole pairs lying in the first Van Hove singularity. A Fano factor of about q = 5 is determined, which drives us to the estimation of biexciton's Auger recombinaison rate B ∈ [0.1; 1] μm · ps−1 . The Biexciton's radiative yield is then estimated of the order of 10−6 .In order to study nanotubes in plasmonic cavities, we developed micro-photoluminescence and dark-field spectroscopy experiments in the optical fiber telecommunication wavelengths (1.3 μm and 1.55 μm). Caracterisation of nanotube samples and plasmonic antenna are presented. Preliminary results on nanotubes inserted in a patch antenna have shown correlation between antenna's position and the spatial distribution of luminescence. Moreover, a change in the carbon nanotube's photoluminescence profile is observed. These results appear to be a turning point in our work. The calibration of our experiment is at its end and studies of optical properties of carbon nanotubes coupled to plasmonic antenna are now on stream in our team.