Premium
Ultrafast spectroscopic imaging of exfoliated graphene
Author(s) -
Grancini Giulia,
Martino Nicola,
Bianchi Massimiliano,
Rizzi Laura Giorgia,
Russo Valeria,
Li Bassi Andrea,
Casari Carlo Spartaco,
Petrozza Annamaria,
Sordan Roman,
Lanzani Guglielmo
Publication year - 2012
Publication title -
physica status solidi (b)
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.51
H-Index - 109
eISSN - 1521-3951
pISSN - 0370-1972
DOI - 10.1002/pssb.201200108
Subject(s) - graphene , ultrashort pulse , picosecond , materials science , ultrafast laser spectroscopy , excited state , absorption (acoustics) , optoelectronics , nanoscopic scale , temporal resolution , scattering , optics , nanotechnology , physics , atomic physics , laser , composite material
In this paper we investigate the carrier cooling dynamics in graphene flakes exploiting ultrafast transient absorption imaging technique. This tool enables us to combine nanoscale spatial resolution and sub‐picosecond (ps) time resolution. It provides many advantages over the standard transient absorption techniques because it directly investigates the excited state dynamics at a local scale that would be usually averaged out. The local dynamics show a photobleaching recovery in the first ps, assigned to cooling by electron–phonon scattering. We found that the photoexcited carrier dynamics is spatially uniform over the micrometer‐sized exfoliated graphene layer.Ultrafast pump–probe technique is combined with an optical microscope to investigate the local excited state dynamics in graphene flakes.