Richard D. James

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Richard James' main area of research is phase transformations in materials - especially shape memory and multiferrroic materials - at large and small scales. This involves the development of mathematical methods for the analysis of materials at atomic and continuum scales, especially the development of multiscale methods for understanding the relation between the behavior of materials on different scales. It also involves advanced methods of bulk synthesis and characterization of new materials in his laboratory, guided by theory. He is currently applying these ideas to the search for interesting materials in several areas:

1. The search for new materials that combine two of the three properties - ferromagnetism, ferroelectricity, shape-memory - particularly by using a highly reversible phase transformation, or, in short, multiferroic materials by phase transformation.
2. The search for new transforming materials with exceptionally low hysteresis and a high degree of reversibility, especially oxide materials with these properties (Oxides are brittle, and there is currently no reversible shape memory oxide.)
3. The use of these multiferroic, phase-change materials in new kinds of energy conversion devices. In particular, members of his group recently discovered a new way to use these materials to convert heat to electricity.
4. The prediction of properties of transforming materials and structures at very small scales. Part of this research involves the study of a remarkable phase transformation that occurs in the tail sheath of bacteriophage T4, a virus that attacks bacteria.
5. The search for new nanostructures based on the concept of "objective structures". These are molecular structures composed of identical molecules such that corresponding molecules "see" the same environment up to orthogonal transformation. These structures have an intriguing relation to the common structures, whether crystalline of not, of most elements in the periodic table, and they are occur often also in biology, especially in viruses. They are also the natural structures to exhibit unusual properties like ferromagnetism, ferroelectricity, and other collective properties, and are especially amenable to methods of synthesis by the process of self-assembly.

Several other current projects extend these ideas to new areas of science and engineering: 
1.  Objective structures motivate the study of new group invariant solutions of Maxwell’s equations. With researchers from TU Munich we have recently found certain “twisted wave” solutions of Maxwell’s equations that interact with helical atomic structures with constructive/destructive interference and potentially could be used as a method of Xray analysis of the structure of helical materials. 
2.  We are developing methods to design morphing origami structures based on the use of ideas from the analysis of phase transformations. 
3.  Our work on hysteresis in phase transformations suggests new ways to understand the origins of magnetic hysteresis in soft magnetic materials.  We are using these ideas to design new soft magnetic alloys. 
4. We are also using ideas from the concept of objective structures to understand the dynamics of nanostructures and gases.  In particular we are developing the method of “objective molecular dynamics”, an exact simulation method for special classes of solutions of molecular dynamics.  Besides providing efficient simulations,  the method links to the Boltzmann equation and offers new insight into non-equilibrium statistical mechanics.