California Institute of Technology Professor of Mechanics and Materials Science Kaushik Bhattacharya investigation of new strategies based on phase engineering of materials have been successfully realized in actuation systems, e.g. in shape memory alloys and relaxor ferroelectrics.
The same underlying principles should be transferable to the development of EM sensors, tunable phase shifters, adaptive optics, optical limiting and energy harvesting devices. The objective of this project is to develop a fundamental understanding and establish the engineering expertise needed to tailor the electrical, optical, or magnetic (EMO) properties of phase transforming materials through the design and implementation of highly reversible, phase-transformations.
This research investigates different approaches to achieving highly reversible phase transformations, including such effects as engineered phase compatibility and frustration. The broad selection of material systems (perovskites and multi-ferroics, Heusler alloys, SMA, and oxy-acid proton conductors), and the design of the studies, will develop a fundamental understanding of the underlying physics that developers need to predict the occurrence of states and the range of behaviors that can be realized within engineered phase transforming materials.
The aim of individual tasks is to develop:
• Perovskites for electrically tunable photonics and RF-to-optical converters;
• Metal-ferroelectric multilayers for negative refractive index material applications (a negative surface-plasmon polariton has been demonstrated to provide NIM behavior in the visible part of the spectrum), light modulators, thermo-magnetic cooling, spintronics and magnetic field sensing;
• Shape memory alloys for large-strain actuators; and
• Proton conducting electrolytes for fuel cells.
As a culmination of the project, the investigators intend demonstrate novel EMO materials and devices.
The investigation is noted in 2009 ARO in Review, a publication of on-going U.S. Army materials and other research.
