Quantum Research Institute Seminar | Unveiling the Invisible: Quantum Defects, Hidden Orders, and the Quest for Dark Matter

Abstract:
At the heart of scalable quantum technologies are interconnected physical systems composed of precisely tailored materials, often operating at their classical and quantum limits. In this talk, I will present our advances in developing and applying theoretical and computational approaches to tackle the unique challenges of predicting and designing quantum phenomena in solid-state systems, connecting atomic-scale information with macroscopic functionality. I will showcase select examples from our group, including the ab initio design of solid-state quantum defects through the establishment of the “Quantum Defects Genome,” leveraging high-throughput materials genomics with state-of-the-art computational techniques. Next, I will discuss our proposal of how emergent phenomena in quantum materials—such as topology, multiferroicity, and superconductivity—are promising platforms for novel quantum sensing schemes aimed at detecting elusive dark matter. I will demonstrate how designer Hamiltonian approaches offer new concepts and enhanced sensitivities for low-mass dark matter detection. Lastly, I will present recent results from our group on the extension of this approach to experimental probes sensitive to ‘hidden’ order parameters, such as the newly proposed ‘altermagnets’, and discuss how these probes provide new quantitative insights into underlying fundamental physics through correlated spectroscopies and microscopies.

Bio:
Dr. Sinéad M. Griffin is a Staff Scientist in the Materials Sciences Division and Molecular Foundry at Berkeley Lab where she leads the quantum materials theory group. Dr. Griffin received her PhD from ETH Zürich in 2014. From 2015-18 she was an SNF postdoctoral fellow at UC Berkeley and Berkeley Lab, before becoming staff scientist. Dr. Griffin’s awards include the Swiss Physical Society Award for General Physics, the Berkeley Lab Director’s Award for Exceptional Scientific Achievement, and the IUPAP Early Career Scientist Prize in Computational Physics. She is also actively involved in promoting science in Africa, and since 2010 has lectured throughout the continent as part of the African School on Electronic Structure: Theory and Applications (ASESMA).