Functional Atomic Force Microscopy
The Functional Atomic Force Microscopy group's mission is to "advance scanning probe microscopies and spectroscopies to capture the nanoscale origins of functional properties in materials for energy and information.â€
The Functional Atomic Force Microscopy (FAFM) group at the Center for Nanophase Materials Sciences (CNMS) is dedicated to advancing the capabilities of scanning probe microscopies. Our team works on exploring new ways to use the sharp and mobile tip of the AFM to induce concentrated strain, electrical, thermal, electromagnetic, and other fields at the surface of material. We use these tools and techniques to characterize their response through minute displacements of the surface, current flow from the tip to the surface, or through optical spectroscopy of light emitted from the tip-surface junction. This allows us to learn about the behavior of materials at fundamental length scales, from 10’s of nm’s to the atomic scale. We leverage and develop cutting-edge data acquisition and control systems to precisely deliver complex electrical, photonic, and thermal signals to the sample and to capture the response.
By scanning the tip across the surface while performing measurements, we can create high-resolution maps of the behavior of advanced materials from multiple stimuli at multiple scales, which can reveal the ways that material inhomogeneity (grain boundaries, defects, multiple phases, interfaces, etc.) can influence macroscale behavior. This gives us insight into the exact mechanisms by which the nano defines the macro, and reveals nuance and complexity that macroscale measurements alone cannot provide. Moreover, in collaboration with the Data NanoAnalytics (DNA) group at the CNMS, we develop and integrate novel artificial intelligence (AI)-based approaches with the microscope to improve the quality and efficiency of imaging and spectroscopy, and to improve analysis of the data we acquire.
Our ultimate goal is to better understand the intricate physics and chemistry that occur at the nanoscale, and to develop new techniques and technologies to help us do so. Furthermore, we aim to deliver these capabilities and offer our expertise to the user community of the CNMS. Through collaborations within and beyond the CNMS, we push the boundaries of what is possible with imaging and spectroscopy through scanning probe microscopy, and expand the scope of what is knowable about the complex workings of the nanoscale world.
Signals to and from the nanoscale
Our group has a rich history of advancing the field of scanning probe microscopy by developing new and innovative driving signals to probe material properties. We strive to improve AFM detection schemes by replacing standard driving signals with novel ones, which can help us overcome challenges related to distinguishing multiple signal sources, spurious signals from the ones we are interested in and for calibration.
The active AFM tip
By using the AFM tip as a source of excitation, we not only "look" at the materials but interrogate them in innovative ways, with fully customized and in-house developed advanced spectroscopies.
Multidimensionality
Advanced spectroscopies require the performance of measurements along many orthogonal axes, and the acquisition of complex sets of data. Multidimensional data processing requires the use of advanced analysis tools. Together with DNA group, we offer Pycroscopy as a tool to expand data analysis beyond imaging and linear spectroscopies.
Control to the user
We work to invent and develop customized scanning probe microscopies by gaining control over AFMs with in-house developed hardware and software. Our extensive knowledge and control over scanning probes enable our users to perform experiments that are unique, pushing the limit of what is can be measured by scanning probes.
Multimodality
Our large portfolio of SPM modes are integrated into a single laboratory, which allows us to combine them in multimodal and correlative studies. Thus we can obtain a deep understanding of the mechanisms that determine the behavior of materials at the nanoscale and how we can influence and control them with all sorts of external fields (bias, light, temperature, and magnetic fields, among others).
Functionalities
We cover multiple areas of materials functionalities for our research and development of new capabilities. Beyond classical short- and long-range force detection covering all sorts of mechanical, electrostatic, electromechanical and magnetic forces, we gain insights into chemical sensitivity by correlated SPM measurements with surface analytical tools such as ToF-SIMS and by combining SPM with light spectroscopies in SNOMs. The expansion of our capabilities towards a Scanning Probes and Photonics laboratory will enable us to explore new phenomena with innovative probe microscopies and spectroscopies.