2019 Medal Winners | francais

The 2019 CAP Medal for Lifetime Achievement in Physics

is awarded to

Douglas Bonn

"I am grateful and humbled by this recognition, which is for work that has always been done in a multitude of strong teams with many other researchers. Canada, and CAP, have always been a welcoming place for such a collaborative research approach." winner citation

The Canadian Association of Physicists (CAP) is pleased to announce that the 2019 CAP Medal for Lifetime Achievement in Physics is awarded to Douglas Bonn, University of British Columbia, for his accomplishments in quantum materials that have advanced our understanding of high-temperature superconductors. announcement

Doug Bonn's main area of research has been unconventional superconductivity, studied through infrared spectroscopy, magnetic measurements, high-field transport measurements, microwave spectroscopy, and scanning tunneling microscopy/spectroscopy. Since 1989, this has included a team effort with Walter Hardy and Ruixing Liang on crystal growth of high temperature superconductors that has fueled their experimental techniques, and many collaborative projects in Canada, the USA, and Europe. Their emphasis has been the growth of very clean materials with few defects of any kind. YBa2Cu3O7-x is the best known because it has led to numerous discoveries over the course of 25 years. More recently this has shifted to growth of high purity LiFeAs and FeSe, amongst the more recently-discovered iron-based superconductors.

This focus on working with stoichiometric compounds that can be grown with very few defects has led to many key results in the field, often because the influence of defects can mask or alter thee properties of materials with unconventional superconducting states. His microwave measurements with Walter Hardy in the 1990s used novel superconducting resonators that provided pivotal evidence for d-wave superconductivity in the cuprates, a result that was a turning point in the field and a direct consequence of working on the cleanest samples. Similar materials-enabled breakthroughs have continued to this day and now include work on iron-based high temperature superconductors and the development of scanning tunneling spectroscopy techniques to study novel superconducting states.

In parallel, Doug Bonn has been developing an innovative approach to teaching introductory physics laboratories, moving away from teaching physics concepts, and instead emphasizing the development of students' ability to reason quantitatively with data. The success of this approach has led to a complete transformation of first-year laboratory teaching at UBC and is being considered at a number of institutions in Canada and the USA. nominator citation

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