Implications of the Physics of Strongly Correlated Systems in X-Ray Scattering of High Energy

• Grant number: 23/10775-1
• Support Opportunities: Regular Research Grants
• Start date: May 01, 2024
• End date: April 30, 2026
• Field of knowledge: Physical Sciences and Mathematics - Physics - Condensed Matter Physics
• Principal Investigator: Sérgio Luiz Morelhão
• Grantee: Sérgio Luiz Morelhão
• Host Institution: Instituto de Física (IF). Universidade de São Paulo (USP). São Paulo , SP, Brazil

Abstract

X-ray crystallography is the most awarded area of applied physics due to its importance in studying the atomic structure of materials and biological systems. With large worldwide investments in new radiation sources, as well as the advent of materials and devices from new technologies, the need of developing new methodologies and mentoring researchers with deep knowledge of x-ray scattering processes have become increasingly imperative in cut-edge researches. To get an idea of the diversity of fields requiring such knowledge, here is a list of recent work in various systems: new magnetic materials, optoelectronic devices, magnetic epitaxial films, topological insulators, nanoparticles for catalysts and bio-imaging by second harmonic generation, van der Waals epitaxy, amino acid crystals with structural alterations, biological molecules, thermoelectric materials, focusing optics and imaging principles for high energy X-rays, and multi panel detectors for X-ray microscopy. These works come from the synergy between many fields of knowledge, bringing together researchers from national and international institutes, but also from the computational resources, procedures, and methodologies in X-ray crystallography that we have developed over the years, such as the recent open source package PyDDT (Python Dynamical Diffraction Toolkit), highlighted publication in the Journal of Applied Crystallography (cover illustration, October/2023 issue). At the current stage of work, mainly regarding materials intended for applications in radioisotope thermoelectric generators for deep space exploration, the used methodologies have produced unprecedented results [36] but restricted to the conventional treatment of periodic crystalline lattices. Local order, or non-random local disorder, either structural as well as vibrational gives rise to diffuse scattering, hence the importance of exploring techniques capable of resolving scattered intensities in three-dimensional reciprocal space outside the exact Bragg conditions. On top of this, there is the need to improve new computational tools for structural modeling, based on diffuse scattering data, and thus better correlate electronic, vibrational and thermoelectric properties of these materials, as detailed in the scope of this proposal. The potential of PyDDT will be applied for studying other systems, such as the effect of metal dopants on radiation damage in amino acid crystals. (AU)