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.

Ultrafast spectroscopic imaging of exfoliated graphene

MARTINO, NICOLA;BIANCHI, MASSIMILIANO;RIZZI, LAURA GIORGIA;RUSSO, VALERIA;LI BASSI, ANDREA;CASARI, CARLO SPARTACO;SORDAN, ROMAN;LANZANI, GUGLIELMO
2012-01-01

Abstract

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.
2012
File in questo prodotto:
File Dimensione Formato  
grancini_pssb_2012.pdf

Accesso riservato

: Post-Print (DRAFT o Author’s Accepted Manuscript-AAM)
Dimensione 3.26 MB
Formato Adobe PDF
3.26 MB Adobe PDF   Visualizza/Apri

I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.

Utilizza questo identificativo per citare o creare un link a questo documento: https://hdl.handle.net/11311/687053
Citazioni
  • ???jsp.display-item.citation.pmc??? ND
  • Scopus 7
  • ???jsp.display-item.citation.isi??? 7
social impact