Bonati, C.Cannizzo, A.Tonti, D.Tortschanoff, A.Van Mourik, F.Chergui, M.2006-02-272006-02-272006-02-27200710.1103/PhysRevB.76.033304https://infoscience.epfl.ch/handle/20.500.14299/225776WOS:00024850080001310959The (sub)-ps relaxation processes in PbSe quantum dots of different sizes were measured by near-IR luminescence upconversion. The early-time spectra are characterized by emission from several low-lying excited states. The direct measurement of the Huang-Rhys factors of the lowest excited states excludes strong electron-phonon coupling in the intraband relaxation. The kinetics point to a fast sequential cascade process between excited states, governed by energy gaps and a quasicontinuous valence-band structure.Excited state (low-lying; of lead selenide quantum dots)Fluorescence up-conversion (near-IR sub-ps; of relaxation in lead selenide quantum dots)IR spectra (near-IR; of lead selenide quantum dots)Band gapValence band (of lead selenide quantum dots)Quantum dot devices (sub-ps near-IR fluorescence upconversion of relaxation in lead selenide)lead selenide quantum dot near IR fluorescence upconversionrelaxationtext::journal::journal article::research article