Bereiche | Tage | Auswahl | Suche | Aktualisierungen | Downloads | Hilfe
HL: Fachverband Halbleiterphysik
HL 17: Two-dimensional Materials I (joint session HL/CPP)
HL 17.3: Vortrag
Dienstag, 2. April 2019, 10:00–10:15, H36
Interplay of bright and dark excitons in transition metal dichalcogenides — •Malte Selig1, Dominik Christiansen1, Florian Katsch1, Ermin Malic2, and Andreas Knorr1 — 1Nichtlineare Optik und Quantenelektronik, Institut für Theoretische Physik, Technische Universität Berlin, Deutschland — 2Chalmers University of Technology, Department of Physics, Göteborg, Sweden
The extraordinarily strong Coulomb interaction in monolayers of transition metal dichalcogenides (TMDs) gives rise to the formation of tightly bound electron hole pairs, excitons, which dominate the optical and electronic properties of these ultrathin materials. In particular, a variety of dark exciton states occurs, including excitons with opposite spins of the constituent carriers [1] and excitons with momenta well above the radiative cone [2]. In this talk, we will address the impact of such dark exciton states to the optical properties of TMDs, including optical lineshape [2,3], luminescence properties [4] and intervalley relaxation. Additionally, we compare the influence of these states on the excitonic linewidth between mono- and bilayer samples [5].
[1] X.-X. Zhang et al., Nature Nanotechnology 12, 883 (2017)
[2] M. Selig et al., Nature Communications 13279 (2016)
[3] D. Christiansen et al., Physical Review Letters 119, 187402 (2017)
[4] M. Selig et al., 2D Materials 5 035017 (2018)
[5] A. Raja et al., Nano Letters, 18 (10), 6135 (2018)