2017/08/30 by Jorge Quereda, Talieh S. Ghiasi, Feitze A. van Zwol +5 · 30 citations
Chemistry · Engineering · Materials Science · Physics and Astronomy · #2D Materials and Applications #Absorption (acoustics) #Absorption edge #Absorption spectroscopy #Band gap #Chemistry #Condensed matter physics #Conduction band #Electron #Exciton #Fermi level #MXene and MAX Phase Materials #Materials science #Molecular physics #Monolayer #Nanotechnology #Optics #Optoelectronics #Perovskite Materials and Applications #Photocurrent #Physics #Spectroscopy #cond-mat.mtrl-sci
paper · pdf · doi:10.1088/2053-1583/aa8aa0
published in 2D Materials 5(1), 015004 (IOP Publishing)
arxiv created 2017/08/30 · openalex publication_date 2017/09/06 · openalex created_date 2017/09/15 · arxiv updated 2018/06/21 · openalex updated_date 2026/08/05
We investigate the excitonic transitions in single- and few-layer MoSe 2 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 MoSe 2 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, . Additionally, we evaluate the thickness-dependent optical bandgap of the fabricated MoSe 2 crystals by characterizing their absorption edge.