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Third-order optical nonlinearities of carbon nanotubes in the femtosecond regime
Auteur(s): Lauret Js, Voisin C., Cassabois G., Tignon J., Delalande C., Roussignol P., Jost O., Capes L.
(Article) Publié:
Applied Physics Letters, vol. 85 p.3572-3574 (2004)
Ref HAL: hal-00546637_v1
DOI: 10.1063/1.1808226
WoS: 000224658100078
Exporter : BibTex | endNote
48 Citations
Résumé: Femtosecond pump-probe experiments have been carried out on an ensemble of single-wall carbon nanotubes deposited on a glass substrate. Measurements of transient changes of transmission and reflection provide an estimate of the real and imaginary parts of the second-order hyperpolarizability of carbon nanotubes. These values are compared with previous measurements and are discussed in the light of a simple model of the optical nonlinearities near the optical band-gap. (C) 2004 American Institute of Physics.
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Acoustic phonon sidebands in the emission line of single InAs/GaAs quantum dots
Auteur(s): Favero I., Cassabois G., Ferreira R., Darson D., Voisin C., Tignon J., Delalande C., Bastard G., Roussignol P., Gerard Jm
(Article) Publié:
Physical Review B, vol. 68 p.233301 (2003)
Ref HAL: hal-00546643_v1
DOI: 10.1103/PhysRevB.68.233301
WoS: 000188186400013
Exporter : BibTex | endNote
124 Citations
Résumé: We present an experimental and theoretical study of the existence of acoustic phonon sidebands in the emission line of single self-assembled InAs/GaAs quantum dots. Temperature-dependent photoluminescence measurements reveal a deviation from a Lorentzian profile with the appearance of lateral sidebands. We obtain an excellent agreement with calculations done in the framework of the Huang-Rhys formalism. We conclude that the only relevant parameter for the observation of acoustic phonon sidebands is the linewidth of the central zero-phonon line. At high temperature, the quasi-Lorentzian quantum dot line appears to be fully determined by the acoustic phonon sidebands.
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Ultrafast carrier dynamics in single-wall carbon nanotubes
Auteur(s): Lauret Jean-Sébastien, Voisin Christophe, Cassabois G., Delalande Claude, Roussignol Philippe, Jost Oliver, Goux-Capes Laurence
(Article) Publié:
Physical Review Letters, vol. 90 p.057404 (2003)
Texte intégral en Openaccess :
Ref HAL: hal-00018421_v1
Exporter : BibTex | endNote
Résumé: Time-resolved carrier dynamics in single wall carbon nanotubes is investigated by means of two-color pump-probe experiments. The recombination dynamics is monitored by probing the transient photo-bleaching observed on the first interband transition of the semi-conducting tubes. The carrier dynamics takes place on a one picosecond time scale which is one order of magnitude slower than in graphite. Transient photo-induced absorption is observed with exactly the same dynamics for non-resonant probe conditions and is interpreted as a global red shift of the $\pi-$plasmon resonance. We show that the opening of the band gap in semi-conducting carbon nanotubes determines the non-linear response dynamics over the whole visible and near-infrared spectrum.
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Disorder-induced photoluminescence up-conversion in InAs/GaAs quantum-dot samples
Auteur(s): Cassabois G., Kammerer C., Sopracase R., Voisin C., Delalande C., Roussignol P., Gerard Jm
(Article) Publié:
Journal Of Applied Physics, vol. 91 p.5489-5491 (2002)
Ref HAL: hal-00546745_v1
DOI: 10.1063/1.1459622
WoS: 000174666600112
Exporter : BibTex | endNote
12 Citations
Résumé: Photoluminescence up-conversion under cw excitation in semiconductor quantum-dot structures is systematically studied in a sample exhibiting a crossover between two-dimensional and three-dimensional (3D) growth modes. We probe the existence of carrier up-conversion by using ultrathin quantum wells close to the quantum-dot layer. We show that the efficiency of the up-conversion is closely related to the disorder induced by the 3D-growth mode of the quantum dots. (C) 2002 American Institute of Physics.
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Efficient acoustic phonon broadening in single self-assembled InAs/GaAs quantum dots
Auteur(s): Kammerer C., Cassabois G., Voisin C., Delalande C., Roussignol P., Lemaitre A., Gerard Jm
(Article) Publié:
Physical Review B, vol. 65 p.033313 (2002)
Ref HAL: hal-00546741_v1
DOI: 10.1103/PhysRevB.65.033313
WoS: 000173448900020
Exporter : BibTex | endNote
45 Citations
Résumé: We report systematic temperature-dependent measurements of photoluminescence excitation spectra in single self-assembled InAs/GaAs quantum dots. We studied the increase with temperature of the excited-state homogeneous linewidth for different quantum dots. We found a correlation between the acoustic phonon broadening efficiency and the background intensity in the photoluminescence excitation spectra. These results demonstrate the interaction of the discrete quantum dot excited states with a quasicontinuum of states and impose severe limitations on the isolated artificial macroatom scheme for a single quantum dot.
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Line narrowing in single semiconductor quantum dots: Toward the control of environment effects
Auteur(s): Kammerer C., Voisin C., Cassabois G., Delalande C., Roussignol P., Klopf F., Reithmaier Jp, Forchel A., Gerard Jm
(Article) Publié:
Physical Review B, vol. 66 p.041306 (2002)
Ref HAL: hal-00546650_v1
DOI: 10.1103/PhysRevB.66.041306
WoS: 000177426400013
Exporter : BibTex | endNote
84 Citations
Résumé: We report systematic linewidth measurements on the fundamental transition of single InGaAs quantum dots. We demonstrate the quenching of the acoustic-phonon dephasing for quantum dots spectrally well separated from the band tail of the wetting layer. We achieve a line narrowing with linewidth of the order of few mueV by tailoring the influence of the electrostatic environment through a decrease of the excess energy in the nonresonant excitation process.
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Interferometric correlation spectroscopy in single quantum dots
Auteur(s): Kammerer C., Cassabois G., Voisin C., Perrin M., Delalande C., Roussignol P., Gerard Jm
(Article) Publié:
Applied Physics Letters, vol. 81 p.2737-2739 (2002)
Ref HAL: hal-00546648_v1
DOI: 10.1063/1.1510158
WoS: 000178318400021
Exporter : BibTex | endNote
80 Citations
Résumé: We report high-resolution spectroscopy by interferometric correlation measurements on the photoluminescence signal of a single quantum dot. We demonstrate that the insertion of a Michelson interferometer in the detection path gives a compact and flexible setup for linewidth measurements. We have used this technique to study self-assembled InAs/GaAs quantum dots. We observe linewidth variations from one quantum dot to another, and we bring evidence of environment effects on the broadening processes. (C) 2002 American Institute of Physics.
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