Exciton-plasmon states in nanoscale materials: Breakdown of the tamm-dancoff approximation

Nano Letters

Volumn 9, Issue 8, 2009, Pages 2820-2824

  Grüning, Myrta ^a,b,c   Marini, Andrea ^a,b   Gonze, Xavier ^a,b  

^a UNIVERSITÉ CATHOLIQUE DE LOUVAIN   (Belgium)

^b UNIVERSITY OF ROME TOR VERGATA   (Italy)

^c UNIVERSITY OF COIMBRA   (Portugal)

Author keywords

[No Author keywords available]

Indexed keywords

AB INITIO APPROACH; AB INITIO CALCULATIONS; AZOBENZENE MOLECULES; ELECTRON HOLE PAIRS; NANO-SCALE MATERIALS;

CARBON NANOTUBES; NANOSTRUCTURED MATERIALS; OPTICAL DATA STORAGE; PLASMONS;

EXCITONS;

EID: 68949093910     PISSN: 15306984     EISSN: None     Source Type: Journal    
DOI: 10.1021/nl803717g     Document Type: Article

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33. Note that our system differs from the experimental one. The latter is far more complex and thus cannot be treated using ab initio methods. In fact, the experimental system consists of a film of aligned bundles of CNTs with an average diameter of 2 nm. In particular the different diameter [2 nm versus ∼0.6 nm of the (8,0) zig-zag CNT] explains the different position of the spectrum onset (the gap is known to decrease with the tube diameter). In spite of these differences, within the full Hamiltonian formulation, the BS equation reproduces well the polarization dependence of the observed photoabsorption spectra.