Development and optimization of single crystal materials with perovskite structure for optoelectronic applications

• Autores: Ismael Fernández Guillén
• Directores de la Tesis: Rafael Abargues López (dir. tes.), Pablo Pérez Boix (codir. tes.), Saïd Agouram (codir. tes.)
• Lectura: En la Universitat de València ( España ) en 2025
• Idioma: inglés
• Número de páginas: 192
• Tribunal Calificador de la Tesis: Sofia Masi (presid.), Sandy Sanchez Alonso (secret.), Alejandro Molina-Sanchez (voc.)
• Programa de doctorado: Doctor en Programa Oficial de Posgrado en Física
• Calificación: Sobresaliente Cum Laude
• Materias:
  • Física
• Enlaces
  • Tesis en acceso abierto en:  webges.uv.es (pdf)  RODERIC 
• Resumen

  • Metal halide perovskites have recently emerged as highly versatile materials for next-generation neuromorphic computing, owing to their unique combination of electronic and ionic conductivity, low-cost processability, and tunable optoelectronic properties. Within this broad field, single-crystal metal halide perovskites stand out due to their superior structural order, minimal trap density, and enhanced stability, making them ideal candidates for high-performance memristive devices. This Thesis focuses on the development, fundamental study, and optimization of perovskite single crystals and thin single crystal-based memristors. The work is structured around two primary objectives: first, to enhance the optoelectronic properties of bulk single crystals through novel surface passivation treatments, and second, the development, fundamental study, and optimization of memristive devices based on thin single crystals. Chapter 3 investigates how surface engineering through laser-induced modification of MAPbBr3 crystals enhances photoluminescence by passivating nonradiative recombination centers, offering insights into optoelectronic processes and crystal lattice dynamics. Chapter 4 introduces a novel thin single-crystal device based on simple architecture that simultaneously overcomes endurance and switching ratio limitations typically observed in polycrystalline and bulk single-crystal memristors. By optimizing the geometry and leveraging the intrinsic ion-electron interplay in MAPbBr3, devices exhibit a LRS/HRS ratio of up to 50 and endurance exceeding 103 cycles, setting new benchmarks in the field. Chapter 5 further explores the impact of compositional engineering by fabricating both mixed-halide thin single crystals, demonstrating multistate non-volatile switching behavior with the use mixed-halide perovskite single crystal-based memristor. These compositional and morphological engineering unlock defect control, enabling precise modulation of key performance parameters. Overall, this work aims to comprehensively develop the properties of perovskite single crystals, encompassing both fundamental material enhancements and the advancement of memristive devices based on single crystal architectures. By integrating compositional and morphological engineering, this study provides essential insights and strategies for the realization of stable, low-power, and high-density memory elements, paving the way for their integration into scalable neuromorphic computing technologies.