Nuri Yazdani

Last Name

Yazdani

First Name

Nuri

ORCID

0000-0001-6593-7601

Organisational unit

03895 - Wood, Vanessa / Wood, Vanessa

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Publications 1 - 10 of 47

Quantifying Diffusion through Interfaces of Lithium-Ion Battery Active Materials
Benedek, Peter; Forslund, Ola K.; Nocerino, Elisabetta; et al. (2020)
ACS Applied Materials & Interfaces
Size, Ligand, and Defect-Dependent Electron-Phonon Coupling in Chalcogenide and Perovskite Nanocrystals and Its Impact on Luminescence Line Widths
Yazdani, Nuri; Volk, Sebastian; Yarema, Olesya; et al. (2020)
ACS Photonics
Soft surfaces of nanomaterials enable strong phonon interactions
Bozyigit, Deniz; Yazdani, Nuri; Yarema, Maksym; et al. (2016)
Nature
Coupling to octahedral tilts in halide perovskite nanocrystals induces phonon-mediated attractive interactions between excitons
Yazdani, Nuri; Bodnarchuk, Maryna I.; Bertolotti, Federica; et al. (2024)
Nature Physics
Understanding the origin of electron-phonon coupling in lead halide perovskites is key to interpreting and leveraging their optical and electronic properties. Here we show that photoexcitation drives a reduction of the lead-halide-lead bond angles, a result of deformation potential coupling to low-energy optical phonons. We accomplish this by performing femtosecond-resolved, optical-pump-electron-diffraction-probe measurements to quantify the lattice reorganization occurring as a result of photoexcitation in nanocrystals of FAPbBr₃. Our results indicate a stronger coupling in FAPbBr₃ than CsPbBr₃. We attribute the enhanced coupling in FAPbBr₃ to its disordered crystal structure, which persists down to cryogenic temperatures. We find the reorganizations induced by each exciton in a multi-excitonic state constructively interfere, giving rise to a coupling strength that scales quadratically with the exciton number. This superlinear scaling induces phonon-mediated attractive interactions between excitations in lead halide perovskites.
Nonequilibrium Thermodynamics of Colloidal Gold Nanocrystals Monitored by Ultrafast Electron Diffraction and Optical Scattering Microscopy
Güzeltürk, Burak; Utterback, James K.; Coropceanu, Igor; et al. (2020)
ACS Nano
Probing Solvent–Ligand Interactions in Colloidal Nanocrystals by the NMR Line Broadening
De Roo, Jonathan; Yazdani, Nuri; Drijvers, Emile; et al. (2018)
Chemistry of Materials
Phonon-Mediated and Weakly Size-Dependent Electron and Hole Cooling in CsPbBr3 Nanocrystals Revealed by Atomistic Simulations and Ultrafast Spectroscopy
Boehme, Simon C.; ten Brinck, Stephanie; Maes, Jorick; et al. (2020)
Nano Letters
A quantitative model for charge carrier transport, trapping and recombination in nanocrystal-based solar cells
Bozyigit, Deniz; Lin, Weyde; Yazdani, Nuri; et al. (2015)
Nature Communications
Improving devices incorporating solution-processed nanocrystal-based semiconductors requires a better understanding of charge transport in these complex, inorganic–organic materials. Here we perform a systematic study on PbS nanocrystal-based diodes using temperature-dependent current–voltage characterization and thermal admittance spectroscopy to develop a model for charge transport that is applicable to different nanocrystal-solids and device architectures. Our analysis confirms that charge transport occurs in states that derive from the quantum-confined electronic levels of the individual nanocrystals and is governed by diffusion-controlled trap-assisted recombination. The current is limited not by the Schottky effect, but by Fermi-level pinning because of trap states that is independent of the electrode–nanocrystal interface. Our model successfully explains the non-trivial trends in charge transport as a function of nanocrystal size and the origins of the trade-offs facing the optimization of nanocrystal-based solar cells. We use the insights from our charge transport model to formulate design guidelines for engineering higher-performance nanocrystal-based devices.
Measuring the Electronic Structure of Nanocrystal Thin Films Using Energy-Resolved Electrochemical Impedance Spectroscopy
Volk, Sebastian; Yazdani, Nuri; Sanusoglu, Emir; et al. (2018)
The Journal of Physical Chemistry Letters
Quantifying the Size-Dependent Exciton-Phonon Coupling Strength in Single Lead-Halide Perovskite Quantum Dots
Zhu, Chenglian; Feld, Leon; Svyrydenko, Mariia; et al. (2024)
Advanced Optical Materials
Optimizing the performance of semiconductors in both classical and quantum applications, not only requires a solid understanding of elementary excitations such as electrons, holes, or bound electron-hole pairs (excitons), but also of their interaction with the host material's vibrational states (phonons). Exciton-phonon coupling is particularly relevant in quantum dots (QDs) of APbX3 lead-halide perovskite (where "A" can be Cs, formamidinium (FA), or methylammonium (MA), and X can be Cl, Br, or I), a new class of semiconductors with a soft crystal structure. Here, they quantify the strength of coupling to interband transitions for both FAPbBr3 and CsPbBr3 QDs, via the magnitude of phonon replicas in their photoluminescence (PL) spectra at cryogenic temperatures. CsPbBr3 QDs exhibit weaker exciton-phonon coupling than similarly sized FAPbBr3 QDs. While the phonon energies are size-independent, the exciton-phonon coupling strength decreases with increasing QD size due to the decreased coupling of the transition to low-energy surface-enhanced phonon modes, consistent withab initio molecular-dynamics (AIMD) simulations. Furthermore, within the harmonic approximation, the size-dependent PL linewidth at room temperature can coarsely be estimated from the low-temperature phonon replica spectrum, highlighting the crucial role of anharmonic effects. These findings contribute to realizing perovskite QD-based devices with narrow and coherent emission for quantum technologies.

Publications 1 - 10 of 47

Nuri Yazdani

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