Synthesis, optoelectronic properties, and charge carrier dynamics of colloidal quasi-two-dimensional Cs<sub>3</sub>Bi<sub>2</sub>I<sub>9</sub> perovskite nanosheets
Sushant Ghimire, Chris Rehhagen, Saskia Fiedler, Urvi Parekh, Rostyslav Lesyuk, Stefan Lochbrunner, Christian Klinke
Abstract
nanosheets using femtosecond transient absorption spectroscopy. The samples are excited with photon energies higher than their bandgap, and the results are interpreted in terms of hot carrier generation (<1 ps), thermalization with local phonons (∼1 ps), and cooling (>30 ps). Further, a relatively slow relaxation of excitons (≳3 ns) at the band edge suggests the formation of stable polarons which decay nonradiatively by releasing phonons.
Topics & Concepts
PhotoexcitationThermalisationPicosecondMaterials scienceNanosecondExcitonPerovskite (structure)Charge carrierRelaxation (psychology)Chemical physicsOptoelectronicsGround stateNanotechnologyCondensed matter physicsExcited stateAtomic physicsChemistryCrystallographyOpticsPhysicsLaserPsychologySocial psychologyPerovskite Materials and Applications2D Materials and ApplicationsSolid-state spectroscopy and crystallography