Abstract:

The heart of condensed matter physics is understanding and exploiting the properties of interacting electrons and atomic nuclei. Thus one recognizes that, at least in principle, virtually all properties of solids can be found given suitable methods for solving this quantum mechanical problem. This is a good news, bad news story. The condensed state is both extraordinarily rich and extraordinarily complex. Perovskite derived oxides are a good example. This class contains among others, the high critical temperature superconductors, the piezoelectrics upon which sonar and medical ultrasound depend, and the colossal magnetoresistive manganites, and yet all these are based on a quite simple structural theme. Understanding the diverse observed phenomena requires a broad range of theoretical efforts, confronted by experiment and, one must admit, a certain element of serendipity. Nonetheless, there is very substantial progress, particularly in understanding the relationships between properties of materials and their microscopic structure and chemistry. Among the engines driving this has been detailed density functional calculations. These bridge the gap between the "gory" details of materials science and general principles, models and concepts about the solid state. In this talk I discuss density functional theory and illustrate how it works by discussing the physics of perovskites using results obtained with it.

Dr.David Singh:

1985 Ph.D in Physics, Univ.of Ottawa, Canada. 1985-88: Postdoc. College of William & Mary, since 1988 Naval Research Laboratory: Position: Head, Theory of Functional Materials Section. Fellow of the American Physical Society. Technology Transfer Award for work on Thermoelectric Materials 1998. Research: First principles calculations and their use to understand, predict and design materials and their properties.