Oral: Diagnosing Topological Properties of Amorphous Bi₂Se₃ from First-Principles

Materials with topological properties, offering lossless transport, robustness to deformations, are excellent candidates for low-power electronics and stable quantum computing. However, both theoretical and experimental work has focused on crystalline topological materials, owing the inherent complexity of modelling and measuring disordered and amorphous systems. Recent experiments have shown that amorphous Bi2Se3 has spin-momentum–locked surface states like those in crystalline structures [1]. In this work, we aim to answer several key questions: What mechanisms drive the topology in amorphous Bi2Se3? How do these properties differ from those in crystalline structures? Does the topology exist in larger scale amorphous structures? To address these, we present results using a suite of computational tools to generate, classify and understanding amorphous topological materials including machine learning-based interatomic potentials to generate larger scale amorphous Bi2Se3, and analysis of their the topology using structural spillage [2], a topological indicator recently proposed for non-crystalline systems. Finally, we use local structural and electronic structure indicators to connect the emergent topology with chemical connectivity in the system.