Research Focus Areas
To elicit the properties one desires from materials requires precise control. This area of research aims to provide that control for complex materials – including illuminating the coupling between material chemistry and defects with epitaxial strain and material properties. Our approach includes aspects of materials design, synthesis, device fabrication, and advanced characterization development and utilization. Recent work has highlighted the intimate connection of material chemistry to the evolution of electronic, thermal, optical, dielectric, ferroelectric, etc. properties, has demonstrated defect-based routes to enhance ordering temperatures and stability, has illuminated both in situ during growth and ex situ processing approaches to deterministically produce specific defect structures that can improve material properties, and has explored routes to characterize such effects in materials.
Driven by recent advances in the production of high-quality thin films of complex-oxide materials, great attention has been given to the use of such approaches to generate new function. As part of this work we explore the use of epitaxial strain, superlattice and artificial heterostructures, compositional and strain gradients, and much more to produce physical effects not expected from classical understanding of materials. Our comprehensive approach includes aspects of materials design, synthesis, device fabrication, and advanced characterization development and utilization. Recent work in this regard has demonstrated emergent magnetism at interfaces, the evolution of polar vortex structures in superlattices, polarization gradients in compositionally-graded films, multi-state switching in ferroelectrics, and much more.
This area of research aims to illuminate one of the most underdeveloped realms of solid state materials science – the physics and control of thermal effects in materials with ferroic order. This work focuses on the development of materials and know-how to enable pyroelectric energy conversion of waste heat to electrical energy, electrocaloric solid state cooling, thermally-driven electron emission, and much more. Our comprehensive approach includes aspects of materials design, synthesis, device fabrication, and advanced characterization development and utilization. Recent work in this regard has provided understanding about the role of domain walls in pyroelectric response, produced novel methods for studying heat-based effects in ferroic thin-film capacitors, and demonstrated colossal energy conversion processes in materials.
Our work is made more productive and fruitful by a number of strong collaborations. The following is a list of some of our major local, national, and global collaborators.
Rice University
Around the Country and the World
University of California, Berkeley
Oak Ridge National Laboratory
Brown University
University of California, Berkeley
Lawrence Berkeley National Laboratory
IISC Bangalore
University of Virginia
Dartmouth University