Observation of bright and dark exciton transitions in monolayer MoSe2 by photocurrent spectroscopy

Jorge Quereda*, Talieh S. Ghiasi, Feitze A. van Zwol, Caspar H. van der Wal, Bart J. van Wees

*Bijbehorende auteur voor dit werk

OnderzoeksoutputAcademicpeer review

12 Citaten (Scopus)
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Samenvatting

We investigate the excitonic transitions in single-and few-layer MoSe2 phototransistors by photocurrent spectroscopy. The measured spectral profiles show a well-defined peak at the optically active (bright) A(0) exciton resonance. More interestingly, when a gate voltage is applied to the MoSe2 to bring its Fermi level near the bottom of the conduction band, another prominent peak emerges at an energy 30 meV above the A(0) exciton. We attribute this second peak to a gate-induced activation of the spin-forbidden dark exciton transition, AD(0). Additionally, we evaluate the thickness-dependent optical bandgap of the fabricated MoSe2 crystals by characterizing their absorption edge.

Originele taal-2English
Artikelnummer015004
Aantal pagina's6
Tijdschrift2D Materials
Volume5
Nummer van het tijdschrift1
DOI's
StatusPublished - 3-okt-2017

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