High-Dimensional Compressive Scanning Transmission Electron Microscopy

Problem Addressed: While modern transmission electron microscopy (TEM) is an incredibly powerful tool for nanoscience and biology, in terms of information theory it is extremely inefficient; the information obtained per electron striking the sample is a small fraction of what information theory says it could be. Not only does this slow down data acquisition, it also greatly increases the radiation dose to the material being studied, which means that today's most advanced atomic-resolution analysis methods can only be readily performed on the most radiation-tolerant materials, leaving most biological systems almost completely in the dark. Especially given the importance of emerging bio/nano hybrid technologies for advanced energy applications, this is a serious problem across a vast range of applications. How the Problem is Being Addressed: Compressive sensing, a fast-growing field that applies data compression theory to the acquisition of data rather than just the storage and transmission of data, can solve the problem by making optimal use of the information provided by each electron. Data are collected in a series of optimized spatial masks instead of pixel by pixel, using the same kinds of advanced high-bandwidth sequencing and control systems that recently produced the IDES-exclusive commercial technology called Movie Mode Dynamic Transmission Electron Microscopy. Combining this with high-dimensional acquisition modes including spectrum imaging, scanning diffraction, tomography, and time resolution should make it possible to acquire vast information-rich high-resolution data sets even on radiation-sensitive organic materials. Commercial Applications and Other Benefits: After demonstrating feasibility in Phase I and developing a fully functional prototype system in Phase II, IDES will be able to start marketing a compressive TEM product immediately to its already-developed early adopter market while simultaneously producing an inexpensive hardware/software TEM accessory that adds compressive sensing capability to virtually any existing TEM, with vast applications in materials science, nanotechnology, energy materials, and biology. Key Words: Compressive Sensing, Electron Microscopy, Transmission Electron Microscopy, Scanning Transmission Electron Microscopy, Spectrum Imaging, Information Theory, Dynamic Transmission Electron Microscopy Summary for Members of Congress: This project will create new commercial technology that dramatically improves the capabilities of electron microscopes, which are essential tools throughout nanotechnology and biomedicine. The technology will allow, for the first time, the most advanced electron microscope techniques to be applied to sensitive organic materials for energy and medical applications.