GOLDEN, Colo., April 5, 2016 – Metallurgical and Materials Engineering Assistant Professor Geoff Brennecka has received an NSF CAREER Award to study how ferroelectric materials – crystalline materials with a built-in polarization that can be reversed under an electric field – respond to this stimulus at a more fundamental level.
This polarization reversal, also known as ferroelectric switching, is well described at low speeds by classic equations, says Brennecka. “But when we try to switch these materials extremely rapidly – e.g., in nanoseconds – their behavior becomes unpredictable.”
A better understanding of how ferroelectric domain walls – boundaries between regions that have the same polarization direction – move around will allow for more efficient materials and improved devices that take advantage of their ferroelectric and piezoelectric properties. Such applications include non-volatile memory, precise positioners found in cameras and automotive fuel injectors, vibrational energy harvesters, and even active catalysts.
One goal of the project is to determine what kinds of features, such as various defects, interfaces, or inclusions, serve as nucleation and/or pinning sites (essentially speed bumps) for this change. “We are approaching this through not just our own structural, chemical, and electrical measurements, but also with collaborators who are experts in techniques that allow us to determine information about the phonons within our materials that set the ultimate speed limit for domain wall motion, ” says Brennecka.
The project, titled “SusChEM: Dynamic Defect Interactions in Ferroelectrics,” will receive $458,000 over five years. It will be integrated into Brennecka’s efforts to expand student engagement, including participation in the annual Discover STEM Camp at Mines and establishment of a hot glass shop in Hill Hall. It will also fund a graduate student, who will be able to work for several weeks each year with collaborators in Virginia and Australia.
The NSF CAREER award is the most prestigious award in support of junior faculty who exemplify the role of teacher-scholars through outstanding research, excellent education, and the integration of education and research within the context of the mission of their organizations.
Brennecka joined Mines in 2014 and is also a member of the Colorado Center for Advanced Ceramics faculty. He holds BS and MS degrees in ceramic engineering from the University of Missouri-Rolla, and a PhD in materials science and engineering from the University of Illinois at Urbana-Champaign.
Contact:
Mark Ramirez, Information Specialist, College of Applied Science & Engineering | 303-384-2622 | ramirez@mines.edu
Karen Gilbert, Director of Public Relations, Colorado School of Mines | 303-273-3541 | kgilbert@mines.edu
