NON-TECHNICAL: In this DMREF project, the rich physics of three large families of artificially structured oxide materials are being studied using a synergistic combination of theoretical and experimental methods. These artificially structured materials, obtained by stacking atomically-thin layers of two or more different compounds, offer enormous flexibility in the choice of constituents, layer thickness, stacking sequence and choice of substrate, which can strongly influence their structure and properties. The approach being developed and applied in this project, integrating computational data-driven search and modeling methods with sophisticated first-principles analysis and state-of-the-art experimental synthesis and characterization of selected materials, allows the design and discovery of novel materials with specified functional properties enhanced and/or distinct from those possible in naturally occurring compounds, thus having the potential to enable transformative technologies.
In this DMREF project, the rich physics of metallic-dielectric perovskite oxide superlattices are being explored through an integrated theoretical-experimental investigation. The principal objective is to map the structure and properties of three selected broad families of superlattices (superlattices of SrMO3 where M=V, Cr, Mn, Fe, Co, Mo or Ru combined with SrTiO3, PbTiO3 or LaMO3) spanning an enormous configuration space. Specifically, the researchers are building on recent advances in high-throughput first-principles infrastructure to develop and demonstrate a guided-sampling high-throughput first-principles approach that uses physically-motivated models to interpret and interpolate first-principles results. Furthermore, their approach compares approximate quantities (that are computed in high-throughput calculations) to those obtained through both high-accuracy computational methods and state-of-the-art experimental synthesis and characterization. This approach is enabling them to identify individual systems with desired functionalities, particularly those related to metal-insulator transitions. In insulating materials the properties of interest are those related to polarization, including piezoresponse and dielectric constant and the size and position of band gaps and band edges. For metallic materials, the thermoelectric properties of these layered systems are especially promising. Intensive theoretical and experimental investigation is validating the theoretically generated structure-property maps, revealing any novel physical phenomena, and pointing the way to potential technological applications. Beyond the systems being studied in this project, the guided-sampling high-throughput approach being developed for this investigation can be applied to other materials design challenges as well. The tight integration of theory and experiment in this project provides a unique opportunity for participants, including graduate, undergraduate and high school students, to develop a broad skill set while participating in cutting edge materials development.
