Results 61 to 70 of about 24,150 (266)
New Journal of Physics, 2018 We present systematic studies of the transient dynamics of GaAs by ultrafast time-resolved reflectivity. In photoexcited non-equilibrium states, we found a sign reverse in reflectivity change Δ R / R , from positive around room temperature to negative at
X C Nie +8 more
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High Charge Carrier Mobility in Non‐Conjugated 3D Covalent Organic Frameworks
Advanced Materials, EarlyView.A non‐conjugated 3D COF constructed via boronate ester linkages from tetraphenylene and pyrene‐based monomers is reported, which exhibits a high charge carrier mobility of 14 ± 1 cm2 V−1 s−1. ABSTRACT π‐Conjugation, π–π stacking, and long‐range order play a central role in determining charge transport efficiency in organic materials.
Joaquín Almarza +11 more
wiley +1 more source
Locating the atoms at the hard-soft interface of gold nanoparticles
Nature CommunicationsSurface structure affects the growth, shape and properties of nanoparticles. In wet chemical syntheses, metal additives and surfactants are used to modify surfaces and guide nanocrystal growth. To understand this process, it is critical to understand how
Weilun Li +13 more
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CrystalsZinc oxide (ZnO) thin films were deposited by radio-frequency reactive magnetron sputtering at a cryogenic substrate temperature of −78 °C to explore a novel low-thermal-budget route for semiconductor growth.
M. A. Ebdah +7 more
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New Journal of Physics, 2014 Excitons in high-purity crystals of Cu _2 O undergo a density-dependent lifetime that opposes Bose–Einstein condensation (BEC). This rapid decay rate of excitons at a density n has generally been attributed to Auger recombination having the form ${\rm d ...
James P Wolfe, Joon I Jang
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Role of the Recombination Zone in Organic Light‐Emitting Devices
Advanced Materials, EarlyView.This review summarizes the critical role of the recombination zone in organic light‐emitting diodes (OLEDs). We highlight that broadening the recombination zone in OLEDs based on emissive layers with balanced charge transport and high photoluminescence quantum yields provides a promising route toward achieving both long operational lifetime and high ...
Yungui Li, Karl Leo
wiley +1 more source
East European Journal of PhysicsThe presence of the effect of thermally activated delayed fluorescence (TADF) in organic light-emitting materials (emitters), manifested in the "collecting" of triplet excitons in organic semiconductor complexes that do not contain noble metals, creates ...
Serhii Melnykov +3 more
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Lattice‐Matched 2D Template Enables Efficient Cesium Tin Halide Perovskite Solar Cells
Advanced Materials, EarlyView.Lattice‐matched 2D perovskite PEA2CsSn2I7 templates the out‐of‐plane growth of inorganic 3D γ‐CsSnI3 along the (110) plane, forming highly oriented 2D/3D tin halide perovskite heterostructures. With reduced trap states and mitigated δ‐phase impurities, the CsSnI3‐based solar cells achieve a power conversion efficiency of 15.27% and maintain stable ...
Hongzhe Anna Xu +15 more
wiley +1 more source
Modulation of delayed fluorescence pathways via rational molecular engineering
Nature CommunicationsOne of the key challenges in developing efficient organic light-emitting diodes (OLEDs) is overcoming the loss channel of triplet excitons. A common approach to mitigate these losses to enhance the external quantum efficiency of OLEDs is employing ...
Sanchari Debnath +7 more
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Photonics meets excitonics: natural and artificial molecular aggregates
Nanophotonics, 2013 Organic molecules store the energy of absorbed light in the form of charge-neutral molecular excitations – Frenkel excitons. Usually, in amorphous organic materials, excitons are viewed as quasiparticles, localized on single molecules, which diffuse ...
Saikin Semion K. +3 more
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