Grüning, Myrta
Marini, Andrea
Gonze, Xavier
[UCL]
Within the Tamm-Dancoff approximation, ab initio approaches describe excitons as packets of electron-hole pairs propagating only forward in time. However, we show that in nanoscale materials excitons and plasmons hybridize, creating exciton-plasmon states where the electron-hole pairs oscillate back and forth in time. Then, as exemplified by the trans-azobenzene molecule and the carbon nanotubes, the Tamm-Dancoff approximation yields errors larger than the accuracy claimed in ab initio calculations. Instead, we propose a general and efficient approach that avoids the Tamm-Dancoff approximation, correctly describes excitons, plasmons, and exciton-plasmon states, and provides a good agreement with experimental results.
Bibliographic reference |
Grüning, Myrta ; Marini, Andrea ; Gonze, Xavier. Exciton-Plasmon States in Nanoscale Materials: Breakdown of the Tamm-Dancoff Approximation.. In: Nano letters, Vol. 9, no. 8, p. 2820-2824 (2009) |
Permanent URL |
http://hdl.handle.net/2078.1/23222 |