Colloquium: Dr. Julian Klein | Massachusetts Institute of Technology

TITLE:  Programming Matter with Electrons

ABSTRACT: Controlling the arrangement of individual atoms has been achieved with lasers, ion traps, and tip-based scanning probe methods and has enabled quantum simulation and computing platforms that transcend naturally occurring configurations of matter. Yet achieving comparable atomic control at scale within a solid remains a foundational challenge, one that could revolutionize the design of artificial matter. Here, I will discuss a fourth approach, deterministic atomic control within a solid using a scanning transmission electron microscope. By developing strategies to deliver electrons with few-picometer accuracy, deterministic control over atomic motion in both space and time is achieved. This enables the creation of 3D defect superlattices in many-nanometer thick CrSBr with user-defined lattice spacing and symmetry, spanning tens of thousands of engineered sites over fields of view exceeding one hundred nanometers, all generated in under an hour. The programmed structures are air-stable and show superlattice Bragg reflections in electron beam diffraction.