Thema der Dissertation:
Excitonic Signatures in Transition-Metal Dichalcogenides: Linking Electronic, Optical, and Vibrational Properties
Excitonic Signatures in Transition-Metal Dichalcogenides: Linking Electronic, Optical, and Vibrational Properties
Abstract: In low-dimensional semiconductors, strong Coulomb interactions give rise to excitons that dominate the optical response. Transition-metal dichalcogenides are ideal systems for studying these effects due to their strong excitonic resonances and tunability in monolayers and heterostructures. In this work, far- and near-field spectroscopy are combined to probe excitonic properties across complementary spatial regimes. Scattering-type near-field optical microscopy resolves the local dielectric response of monolayer WS₂ on Au and enables nanoscale observation of an interlayer exciton in MoSe₂/WSe₂ heterostructures at 1.35 eV. Complementary resonant Raman spectroscopy, supported by density-functional-theory calculations, reveals interlayer exciton–phonon coupling between the MoSe₂ A₁g phonon and the WSe₂ A exciton. Together, these results link nanoscale optical response to the underlying excitonic and dielectric properties of TMDC monolayers and heterostructures.
Time & Location
Aug 21, 2026 | 11:00 AM
Hörsaal A (1.3.14)
(Fachbereich Physik, Arnimallee 14, 14195 Berlin)