Room Temperature Magnetoelectric & Multiferroic Films and Composites for novel Devices

点击翻译按钮获取中文摘要

The next generation of miniaturized devices will increasingly rely on "smart materials", materials with the uncanny ability to respond to an external stimulus by abruptly changing their properties in a reversible manner. Multiferroics, exhibiting at once, a magnetic and a ferroelectric ordering are potentially such smart materials. While the interplay between magnetic ordering and ferroelectricity in these compounds is presently one of the unanswered fundamental questions in condensed matter physics, the occurrence of both orders simultaneously is rare and very often occurs at low temperature. The recent emergence of thin films and nanostructures of materials with good multiferroic properties at room temperature has been a turning point opening the way for using multiferroics/magnetoelectrics into novel integrated devices, in areas such as sensing, energy conversion, as well as photonics and high-frequency electronics for telecommunication.This research program will focus on investigating exclusively single phase and in-situ forming nanocomposites systems that are multiferroic at room temperature. It will concentrate on studying their magnetoelectric coupling as well as their high-frequency dynamic behavior, which are key properties for applications. The room temperature multiferroic epitaxial thin films of the Bi-based double perovskites and in-situ generated multiferroic nanocomposites discovered and developed in my group will be further studied, while new room temperature multiferroic systems will be investigated as well, such as doped bismuth ferrite and tetragonal tungsten bronze/barium ferrite. Proof-of-concept devices will be fabricated with the room temperature magnetoelectric films synthesized and studied. Finally, the electromechanical properties of nanocrystalline cellulose individual fibers will be studied at the nanoscale using piezoresponse force microscopy, a step toward a cheap novel piezoelectric technological materials based on a resource abundant in Canada and in the world. This research program will provide a stimulating training environment at the leading edge of today's research in the field of multiferroic and magnetoelectric smart materials.