Exotic Magnetism in Geometrically Frustrated Magnets Under Extreme Conditions

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Many of the technological advances of the last century, from the integrated circuit to the magnets used in magnetic resonance imaging, have been due to an understanding of the interplay between the electronic, magnetic, and lattice degrees of freedom in solids. Despite this staggering level of progress, challenges remain towards future innovations which are limited by an understanding of many-body effects and quantum mechanics. Many of the developments of the future are likely to be found in so-called quantum materials, which show exotic states of matter when exposed to extreme conditions such as high magnetic fields, low temperatures, or high applied pressures.  High temperature superconductors are prominent examples of this class of materials. The application of pressure to quantum materials as a probe of these new states of matter has been a successful route towards understanding these compounds.  Chemical pressure, for example, through the chemical substitution of larger or smaller cations into established solid state structures, has been a successful route to elucidating complicated electronic and magnetic phenomena in solids.  This has led to the exploration of entirely new electronic states of matter.  The synthesis of new materials via high pressure methods has been a rapidly growing area of research, and has helped to widely expand the number of known geometrically frustrated magnets.  Using geometrical frustration under extreme conditions as a central theme, the PI will take the following multifaceted approach to the study of quantum materials: (1) Expansion of high pressure synthesis techniques: A collaboration has been made between the University of Winnipeg and the Centre for Science at Extreme Conditions (CSEC) at the University of Edinburgh to synthesize new materials under high pressure. (2) Characterization of the thermodynamic properties of new materials: Newly synthesized materials will continue to be studied using the x-ray diffraction and low temperature capabilities at the University of Winnipeg, and also using the equipment at the National High Magnetic Field Laboratory (Tallahassee, Florida), and the University of Edinburgh (CSEC). (3) Structural and magnetic studies of new materials using neutron scattering, x-ray scattering and muon spin relaxation: The current research program of the PI using probes such as neutron scattering, x-ray scattering, and muon spin relaxation will be expanded to incorporate high pressure probes. (4) Expansion of crystal growth techniques: High pressure crystal growth techniques will be explored using the high pressure image furnaces at the Oak Ridge National Laboratory.  These four areas of growth will be complemented by an educational program that involves not only undergraduate students at the University of Winnipeg, but also graduate students through the PIs joint appointment at the University of Manitoba and McMaster University.