title: The mass load effect on the resonant acoustic frequencies of colloidal semiconductor nanoplatelets.
abstract: Resonant acoustic modes of ultrathin CdS and CdSe colloidal nanoplatelets (NPLs) with varying thicknesses were probed using low frequency Raman scattering. The spectra are dominated by an intense band ascribed to the thickness breathing mode of the 2D nanostructures. The measured Raman frequencies show strong deviations with respect to the values expected for simple bare plates, all the more so as the thickness is reduced. The deviation is shown to arise from the additional mass of the organic ligands that are bound to the free surfaces of the nanoplatelets. The calculated eigen frequencies of vibrating platelets weighed down by the mass of the organic ligands are in very good agreement with the observed experimental behaviours. This finding opens up a new possibility of nanomechanical sensing such as nanobalances.
authors.affiliation: Institut Lumière Matière, Université de Lyon, Université Claude Bernard Lyon 1, UMR CNRS 5306, 69622 Villeurbanne, France. alain.mermet@univ-lyon1.fr.
authors.forename: Adrien
authors.initials: A
authors.lastname: Girard
authors.affiliation: Laboratoire Interdisciplinaire Carnot de Bourgogne, UMR 6303 CNRS-Université de Bourgogne Franche Comté, 9 Av. A. Savary, BP 47 870, F-21078 Dijon Cedex, France.
authors.forename: Lucien
authors.initials: L
authors.lastname: Saviot
authors.affiliation: Laboratoire de Physique et d'Etudes des Matériaux, CNRS, Université Pierre et Marie Curie, ESPCI, 10 rue Vauquelin, 75005 Paris, France.
authors.forename: Silvia
authors.initials: S
authors.lastname: Pedetti
authors.affiliation: Laboratoire de Physique et d'Etudes des Matériaux, CNRS, Université Pierre et Marie Curie, ESPCI, 10 rue Vauquelin, 75005 Paris, France.
authors.forename: Mickaël D
authors.initials: MD
authors.lastname: Tessier
authors.affiliation: Institut Lumière Matière, Université de Lyon, Université Claude Bernard Lyon 1, UMR CNRS 5306, 69622 Villeurbanne, France. alain.mermet@univ-lyon1.fr.
authors.forename: Jérémie
authors.initials: J
authors.lastname: Margueritat
authors.affiliation: Institut Lumière Matière, Université de Lyon, Université Claude Bernard Lyon 1, UMR CNRS 5306, 69622 Villeurbanne, France. alain.mermet@univ-lyon1.fr.
authors.forename: Hélène
authors.initials: H
authors.lastname: Gehan
authors.affiliation: Institut Lumière Matière, Université de Lyon, Université Claude Bernard Lyon 1, UMR CNRS 5306, 69622 Villeurbanne, France. alain.mermet@univ-lyon1.fr.
authors.forename: Benoit
authors.initials: B
authors.lastname: Mahler
authors.affiliation: Laboratoire de Physique et d'Etudes des Matériaux, CNRS, Université Pierre et Marie Curie, ESPCI, 10 rue Vauquelin, 75005 Paris, France.
authors.forename: Benoit
authors.initials: B
authors.lastname: Dubertret
authors.affiliation: Institut Lumière Matière, Université de Lyon, Université Claude Bernard Lyon 1, UMR CNRS 5306, 69622 Villeurbanne, France. alain.mermet@univ-lyon1.fr.
authors.forename: Alain
authors.initials: A
authors.lastname: Mermet