Berlin 2015 – wissenschaftliches Programm
TT 80.8: Vortrag
Mittwoch, 18. März 2015, 17:00–17:15, MA 005
Newly observed first-order resonant Raman modes in few-layer molybdenum disulfide — •Nils Scheuschner, Roland Gillen, Matthias Staiger, and Janina Maultzsch — Technische Universität Berlin, Institut für Festkörperphysik, Hardenbergstr. 36, 10623 Berlin
We show measurements of two newly observed first-order Raman modes in few-layer MoS2 with phonon energies of 286 cm−1 and 471 cm−1. These modes are strongly resonant and appear only when using excitation energies above ≈ 2.4 eV. At 2.7 eV, their intensity is comparable to the second-order Raman modes; their absence thus provides an easy and accurate method to identify single-layer MoS2. At UV excitation, the intensity of the new modes is even larger than the typically examined A′1/A1g and E′/Eg modes. We provide a systematic analysis of the phonon modes, their symmetries, and their frequencies in few-layer materials, including the newly observed modes.