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Research in the Luke group focusses on experimental studies of so-called quantum materials which include exotic superconductors and novel magnetic systems. Systems which combine superconductivity with magnetism are of special interest.

At present, our group is actively studying a number of systems including pnictide and cuprate high temperature superconductors in addition to a variety of so-called heavy fermion systems where electron-electron interactions results in extremely large carrier effective masses. Some of these heavy fermion systems exhibit a number of exotic ordering phenomena ranging from magnetic order and superconductivity to so-called hidden order where a thermodynamic phase transition is apparent in a range of measurements, but the nature of the ordered state is unknown.
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We have an ongoing major interest in magnetic systems where geometrical frustration and/or low dimensionality conspire to preclude conventional magnetic order, allowing more exotic magnetic ground states to emerge. An illustration of this type of phenomena is provided by Sr3Cr2O8. This system consists of a loosely connected network of spin dimers. In the presence of large magnetic fields the system undergoes a quantum phase transition from a collective singlet non-magnetic ground state to an ordered state which can be described as a Bose-Einstein condensate of magnetic excitations (magnons).