Regensburg 2016 – wissenschaftliches Programm
Bereiche | Tage | Auswahl | Suche | Aktualisierungen | Downloads | Hilfe
HL: Fachverband Halbleiterphysik
HL 16: Graphene: Transport (Joint session of DS, HL and TT, organized by HL)
HL 16.5: Hauptvortrag
Montag, 7. März 2016, 16:15–16:45, H17
Thermodynamic picture of ultrafast conduction in graphene — •Dmitry Turchinovich1, Zoltan Mics1, Klaas-Jan Tielrooij1,2, Ivan Ivanov1, Xinliang Feng1, Klaus Müllen1, and Mischa Bonn1 — 1Max Planck Institute for Polymer Research, 55128 Mainz, Germany — 2ICFO, 08860 Barcelona, Spain
Graphene has very high steady-state conductivity, which, however, does not hold in the regime of ultrafast, sub-picosecond electric fields corresponding to the terahertz (THz) frequencies. Here we show that in graphene, the electron conduction on an ultrafast timescale is determined by a simple thermodynamic balance maintained within its electronic system acting as a thermalized electron gas [1]. The energy of ultrafast electric currents passing trough graphene is near-instantaneously converted into the thermal energy of its entire charge carrier population, thereby raising the electronic temperature and reducing the chemical potential. The interplay between electron heating and cooling dynamics in graphene ultimately defines its ultrafast conductivity. We demonstrate that this simple thermodynamic picture describes very well the THz linear, nonlinear, and photo-induced conductivity of this remarkable material [1-3].
[1] Z. Mics, K.-J. Tielrooij, K. Parvez, S. A. Jensen, I. Ivanov, X. Feng, K. Müllen, M. Bonn, and D. Turchinovich, Nat. Commun. 6, 7655 (2015). [2] S. A. Jensen, Z. Mics, I. Ivanov, H. S. Varol, D. Turchinovich, F. H. L. Koppens, M. Bonn, and K. J. Tielrooij, Nano Lett. 14, 5839 (2014). [3] I. Ivanov, M. Bonn, Z. Mics, and D. Turchinovich, EPL - Europhys. Lett. 111, 67001 (2015).