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arXiv · 1712.05219

Molecule signatures in photoluminescence spectra of transition metal dichalcogenides

Maja Feierabend·Gunnar Berghaeuser·Malte Selig·Samuel Brem·Timur Shegai·Siegfried Eigler·Ermin Malic
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Abstract

Monolayer transition metal dichalcogenides (TMDs) show an optimal surface-to-volume ratio and are thus promising candidates for novel molecule sensor devices. It was recently predicted that a certain class of molecules exhibiting a large dipole moment can be detected through the activation of optically inaccessible (dark) excitonic states in absorption spectra of tungsten-based TMDs. In this work, we investigate the molecule signatures in photoluminescence spectra in dependence of a number of different experimentally accessible quantities, such as excitation density, temperature as well as molecular characteristics including the dipole moment and its orientation, molecule-TMD distance, molecular coverage and distribution. We show that under certain optimal conditions, even room temperature detection of molecules can be achieved.

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Maja Feierabend, Gunnar Berghaeuser, Malte Selig, Samuel Brem, Timur Shegai, Siegfried Eigler, Ermin Malic. 2017-12-14. Molecule signatures in photoluminescence spectra of transition metal dichalcogenides. https://doi.org/10.1103/physrevmaterials.2.014004

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