Thermoelectrics Materials and Devices

The structural and compositional studies of single nanowires by transmission electron microscopy have been conducted with the help of Professor Ron Gronsky (Dept. of Materials Science and Engineering, UC Berkeley) at microscopes in the National Center for Electron Microscopy (NCEM). The information gained from single wire characterization has helped to inform nanowire synthesis and will aid in correlating efficiency improvements with structure.

As the quality of our nanowire arrays improves, the thermal and electrical property measurements are needed to understand any increase in the thermoelectric efficiency. We collaborate with both academic and industrial groups to test new property measurement techniques and devices designed specifically with the challenges of nanowire measurements in mind. We have worked with Professor Arun Majumdar (Mechanical Engineering, UC Berkeley) and his students, to measure the thermal properties of both nanowire arrays and single nanowires. We currently work with Marlow Industries to measure the overall efficiency of our nanowire arrays incorporated into TE couples.

Project funded by the Office of Naval Research (ONR), Lockheed-Martin Corporation, and NASA.

Magnetoresistive Materials

Our work on chalcogenide spinels is part of an NSF Nanoscale Interdisciplinary Research Team on Complex Magnetic Materials and Devices. The lead investigator of the NIRT is Prof. Yuri Suzuki here in the Materials Science and Engineering department at UCB; we work closely with the Suzuki group on the materials fabrication and characterization. As the project progresses, we anticipate further interaction with the other principal investigators on the NIRT: theorist Prof. William Butler (Alabama) and experimentalists  Prof. Yves Idzerda (Montana State) and Prof. Jagadeesh Moodera (MIT).

Studies on magnetoresistive nanowire synthesis and characterization are supported by a generous grant from the National Science Foundation. Magnetoresistive measurements on our nanowire arrays are being performed in collaboration with the Suzuki group (UC Berkeley) through the expertise of Rajesh Chopdekar.