Effects of surface functionalization and size of MXene-based quantum dots on their optical properties: the exciton confinement matters
Barbora Vénosová⬡, František Karlický
Abstract
QDs shrink. In addition, small quantum dots with a lateral size of ∼1-2 nm exhibit strong quantum coupling effects, accompanied by an increase in exciton binding energy with delocalization across the quantum dot. The binding energy of the first exciton in MXQDs can achieve up to 75% of its energy gap (in corresponding 2D materials, the typical value is around 25%), which critically influences (increases and shifts) optical absorption.
Topics & Concepts
Quantum dotDelocalized electronExcitonMaterials scienceSurface modificationBand gapAbsorption (acoustics)Binding energyDensity functional theoryPotential wellMolecular physicsBiexcitonAbsorption spectroscopyBlueshiftChemical physicsElectro-absorption modulatorOptoelectronicsCondensed matter physicsElectronic structureQuantum dot laserSurface statesTime-dependent density functional theoryQuantumCoupling (piping)NanotechnologyAtomic physicsVisible spectrumChemistryDensity of statesSurface energySurface (topology)MXene and MAX Phase Materials2D Materials and ApplicationsAdvanced biosensing and bioanalysis techniques