MSD scientists explore the dynamical properties of energy, matter, and charge as they encounter defects or traverse complex interfaces in materials to deliver new functionality.
Storage, transport, and transduction between energy and information are mediated by materials defects and boundaries or interfaces. Batteries convert electricity into chemical bonds by moving ions across interfaces. Spin-momentum locking in topological insulators offers a means to generate new spintronic functionality. Resistive states of oxide defect complexes can store data in memristor platforms for novel memory. From a fundamental science perspective, interfaces such as these govern the behavior of two-dimensional electron gases, Schottky barriers, Majorana states in topological superconductors and composites, and mixed electronic/ionic transport in electrochemical systems. Defects offer nucleation sites for electronic or magnetic inhomogeneity. In the case of objects like nitrogen-vacancy centers, skyrmions and vortices, or resistive oxide filaments, the spin or charge defect itself can be the functional unit. Understanding the fundamental static and operando properties imparted through such interfaces and/or defects is a key element of our strategy, requiring exquisite control of the synthesis and measurement of key structural and physical properties that define their behavior, supported by theoretical modeling of these processes from atomistic to coarse-grained scales.
Interface and defect science are key elements of Argonne MSD science, ranging from electrochemistry to correlated electron physics to magnetic and ferroelectric nanostructures and memristive behavior. We have developed or have access to a unique array of tools for conducting in situ synchrotron synthesis of real interfaces and for probing or imaging defects at their natural length scales. In addition, we probe in situ the behavior of these materials at natural length and time scales, and we bring world-class experimental and modeling capabilities in nanostructured magnetic systems. A reciprocal relationship with the Joint Center for Energy Storage Research (JCESR), a DOE Energy Innovation Hub, cemented through shared staff, amplifies both our impact and that of the Hub in exploration of electrochemical interfaces.