Topological Quantum Effects Ruled by Local Defects

• Grant number: 25/13106-9
• Support Opportunities: Scholarships in Brazil - Post-Doctoral
• Start date: August 01, 2025
• End date: July 31, 2027
• Field of knowledge: Physical Sciences and Mathematics - Physics - Condensed Matter Physics
• Principal Investigator: Adalberto Fazzio
• Grantee: Emmanuel Victor Caires Lopes
• Host Institution: Centro Nacional de Pesquisa em Energia e Materiais (CNPEM). Ministério da Ciência, Tecnologia e Inovação (Brasil). Campinas , SP, Brazil
• Associated research grant: 23/09820-2 - Materials by design: from quantum materials to energy applications, AP.TEM

Abstract

The introduction of local defects in materials has been a historic experimental route for controlling their properties. This includes impurities in semiconductors, which affect their electronic and optical properties, as well as catalytic active sites in metals. New topological phases of matter are emerging with promising applications in spintronics and quantum computing. A particular class of such materials, known as topological insulators, exhibit bulk insulating behavior while having metallic surface channels constrained by a system's symmetry. The surface states are robust against defects that do not violate this symmetry. However, in a recent study, we have shown that the presence of defects can determine the manifestation of topological non-trivial phases. This project aims to push the frontier of systems by employing data-science analysis, high-throughput calculations, and machine learning algorithms to explore the induction of non-trivial topological phases in known trivial insulators through the introduction of local defects. (AU)