Search results for "PEROVSKITE"
showing 10 items of 458 documents
Purcell Enhancement and Wavelength Shift of Emitted Light by CsPbI3 Perovskite Nanocrystals Coupled to Hyperbolic Metamaterials
2020
Manipulation of the exciton emission rate in nanocrystals of lead halide perovskites (LHPs) was demonstrated by means of coupling of excitons with a hyperbolic metamaterial (HMM) consisting of alternating thin metal (Ag) and dielectric (LiF) layers. Such a coupling is found to induce an increase of the exciton radiative recombination rate by more than a factor of three due to the Purcell effect when the distance between the quantum emitter and HMM is nominally as small as 10 nm, which coincides well with the results of our theoretical analysis. Besides, an effect of the coupling-induced long wavelength shift of the exciton emission spectrum is detected and modeled. These results can be of i…
On the Way to Optoionics
2020
Discussions with Michael Grätzel, Ursula Röthlisberger, Robert A. Evarestov and Bettina V. Lotsch are gratefully acknowledged.
Optoelectronic devices based on caesium lead halide perovskite nanocrystals
2020
Tradicionalmente, la implementación de materiales activos en circuitos fotónicos integrados se ha basado en la utilización de semiconductores III-V y vidrios y materiales ferroeléctricos dopados con iones de tierras raras. Sin embargo, en la actualidad existe una alternativa basada en (nano) materiales sintetizados por técnicas de química coloidal. La posibilidad de procesar nanomateriales en solución permite fabricar semiconductores con propiedades ópticas (emisión, absorción, dispersión de luz) que pueden diseñarse durante la síntesis. Además, su naturaleza coloidal permite integrarlas en cualquier arquitectura óptica mediante sencillas técnicas de impresión en tinta. En este contexto, lo…
Octahedral Tilting in Homologous Perovskite Series CaMoO3-SrMoO3-BaMoO3 Probed by Temperature-Dependent EXAFS Spectroscopy
2022
This research was funded by the State Education Development Agency project No. 1.1.1.2/VIAA/3/19/444 (agreement No. 1.1.1.2/16/I/001) realized at the Institute of Solid State Physics, University of Latvia; the Institute of Solid State Physics, University of Latvia, as the Center of Excellence received funding from the European Union’s Horizon 2020 Framework Programme H2020-WIDESPREAD-01-2016-2017-TeamingPhase2 under grant agreement No. 739508, project CAMART2.
Low dimensional perovskite: synthetic methods and application in optoelectronics
2020
Through the end of contribute to the next generation of photovoltaics and light emitting devices the preparation of no-expensive and high quality materials with high PLQY and reduced non-radiative recombination is crucial. For such a reason the thesis is focus on the develop of high optoelectronic potential hybrid perovskite material and on their processing methods. In the different Chapters, various low dimensional perovskite synthetic approaches and their application are investigated. In the Chapter 2, a low dimension quasi-2D perovskite with a remarkable PLQY was prepared thanks to interplay of different fabrication approaches such us altered stoichiometry, solution engineered deposition…
Oxygen Vacancy Formation and Migration within the Antiphase Boundaries in Lanthanum Scandate-Based Oxides: Computational Study.
2022
The study was performed with the financial support from the Latvian Council of Science under the grant agreement LZP-2020/2-0009. Calculations were performed at the HLRS, University of Stuttgart, within the project 12939 DEFTD. The Institute of Solid State Physics, University of Latvia (Latvia), as the Centre of Excellence has received funding from the European Union’s Horizon 2020 Frame-work Programme H2020-WIDESPREAD-01-2016-2017-Teaming Phase2 under grant agreement No. 739508, project CAMART2.
Optical Amplification in Hollow-Core Negative-Curvature Fibers Doped with Perovskite CsPbBr
2019
We report a hollow-core negative-curvature fiber (HC-NCF) optical signal amplifier fabricated by the filling of the air microchannels of the fiber with all-inorganic CsPbBr3 perovskite nanocrystals (PNCs). The optimum fabrication conditions were found to enhance the optical gain, up to +3 dB in the best device. Experimental results were approximately reproduced by a gain assisted mechanism based on the nonlinear optical properties of the PNCs, indicating that signal regeneration can be achieved under low pump powers, much below the threshold of stimulated emission. The results can pave the road for new functionalities of the HC-NCF with PNCs, such as optical amplification, nonlinear frequen…
Computational studies on systems derived from barium zirconate perovskite structure
2010
In solid oxide protonic conductors, proton diffusion is mainly driven by phonon-assisted dynamics, for this, becoming important local distorsion studies on the lattice, in order to detail the protonic conduction mechanism hence to improve performances of the related materials. Here, the protonic conductor Y:BaZrO3 was studied by means of DFT calculations, using new tetravalent substitution models.
Characterization of the pressure induced Ringwoodite to Mg-perovskite+Mg-wuestite phase transition by Catastrophe Theory
2010
Unravelling the Photocatalytic Behavior of All-Inorganic Mixed Halide Perovskites: The Role of Surface Chemical States
2019
Within the most mesmerizing materials in the world of optoelectronics, mixed halide perovskites (MHPs) have been distinguished because of the tunability of their optoelectronic properties, balancing both the light-harvesting efficiency and the charge extraction into highly efficient solar devices. This feature has drawn the attention of analogous hot topics as photocatalysis for carrying out more efficiently the degradation of organic compounds. However, the photo-oxidation ability of perovskite depends not only on its excellent light-harvesting properties but also on the surface chemical environment provided during its synthesis. Accordingly, we studied the role of surface chemical states …