High magnetic field and neutron scattering measurements of magnetic materials

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The proposed research program depends on recent additions to my new laboratory at St. Francis Xavier University, my role at the Spallation Neutron Source (SNS), and my collaboration in the Advanced Foods and Materials Network (AFMNet).  My laboratory now includes an easy-to-use but powerful magnet, which can reach very high magnetic fields.  The SNS being built in Oak Ridge, Tennessee, will be the most powerful and modern scientific research facility of its type in the world, and I am personally involved in the development of one of the instruments.  AFMNet is a national collaboration of natural scientists, engineers, health researchers, social scientists, and lawyers working on various facets of food and bio-material advances.  My first research thrust is looking at magnetic materials.  One group of materials has a wavelike magnetic structure, and I want to see how that structure is affected by replacing atoms with different ones and by applying a magnetic field.  Studying these relatively simple materials will tell us more about related, complicated materials with important practical applications.  Another group has materials which could be used as a magnetic sensors, in computer hard drives, or possibly in new, faster types of electronics.  Again, I will be looking for effects caused by magnetic fields, but also by squeezing the material.  The other group is shape-memory alloys, which can be bent and return to their original shape if heated, but also expand and contract in a magnetic field.  Neutron scattering at either the Canadian Neutron Beam Centre in Chalk River or the SNS can be used to look at the magnetic structures and interactions, which are closely related to their interesting properties.  In AFMNet, my team is studying small spheres (roughly 100 billionths of metre across) formed from the molecules that make up the outer walls of bacteria.  Small-angle neutron scattering acts as a powerful microscope to see how these spheres behave as they interact with simple chemicals or with candidates for new antibiotics.  Studying this interaction and seeing if we can describe it using physical models is very important, since bacteria play such an important role in human health.