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Direct measurement of the exciton binding energy and effective masses for charge carriers in organic–inorganic tri-halide perovskites
Direct measurement of the exciton binding energy shows that the impressive performance of perovskite solar cells arises from the spontaneous generation of free electrons and holes after light
Approaching the dirac point in high-mobility multilayer epitaxial graphene.
Multilayer epitaxial graphene is investigated using far infrared transmission experiments in the different limits of low magnetic fields and high temperatures, finding the well-defined Landau level quantization up to room temperature at magnetic fields below 1 T, a phenomenon unusual in solid state systems.
Determination of the exciton binding energy and effective masses for methylammonium and formamidinium lead tri-halide perovskite semiconductors
The family of organic–inorganic halide perovskite materials has generated tremendous interest in the field of photovoltaics due to their high power conversion efficiencies. There has been intensive
Collective vibrational modes in biological molecules investigated by terahertz time-domain spectroscopy.
Well-resolved absorption spectra of biological molecules in the far-IR (FIR) spectral region recorded by terahertz time-domain spectroscopy (THz-TDS), which can provide a direct fingerprint of the molecular structure or conformational state of a compound.
Carrier relaxation in epitaxial graphene photoexcited near the Dirac point.
The experiments complemented by microscopic modeling reveal that the carrier relaxation is significantly slowed down as the photon energy is tuned to values below the optical-phonon frequency; however, owing to the presence of hot carriers, optical-Phonon emission is still the predominant relaxation process.
Optical manipulation of the exciton charge state in single-layer tungsten disulfide
Raman scattering and photoluminescence (PL) emission are used to investigate a single layer of tungsten disulfide (WS${}_{2}$) obtained by exfoliating $n$-type bulk crystals. Direct gap emission with
Impact of the Halide Cage on the Electronic Properties of Fully Inorganic Cesium Lead Halide Perovskites
Perovskite solar cells with record power conversion efficiency are fabricated by alloying both hybrid and fully inorganic compounds. While the basic electronic properties of the hybrid perovskites
Defect Healing and Charge Transfer-Mediated Valley Polarization in MoS2/MoSe2/MoS2 Trilayer van der Waals Heterostructures.
This work shows that the optical quality of CVD-grown MoSe2 is completely recovered if the material is sandwiched in MoS2/MoSe 2/MoS2 trilayer van der Waals heterostructures, and shows that this remarkable and unexpected result is due to defect healing.
Dark excitons and the elusive valley polarization in transition metal dichalcogenides
A rate equation model for the dark and bright excitons kinetics is proposed which explains the wide variation in the observed degree of circular polarization of the PL emission in different TMDs
High-energy limit of massless Dirac fermions in multilayer graphene using magneto-optical transmission spectroscopy.
Polarization-resolved measurements of multilayer graphene in high magnetic fields show no observable electron-hole asymmetry, in good agreement with the theoretical model, which includes trigonal warping of the Fermi surface and higher-order band corrections.