University of Waterloo
200 University Avenue West
Waterloo, Ontario, Canada N2L 3G1
Phone: (519) 888-4567 ext 32215
Fax: (519) 746-8115
Department of Physics and Astronomy, University of British Columbia
Dr. Bonn's area of research is the study of high temperature superconductors and other quantum materials. A central goal of this program is to understand the origin of high temperature superconductivity, in the cuprates and in the newer Fe-based compounds. These are spectacular manifestations of a diverse group of materials known as strongly correlated electron systems, materials that develop intricate and puzzling properties because their electrons interact strongly with one another, unlike simpler electronic materials such as silicon or copper. Recent projects in the superconductivity group fall into the topics noted below, with plenty of scope for students to combine these and stretch in new directions.
The discovery of high temperature superconductivity in a family of iron-based compounds has generated a new wave of research into unconventional superconductivity. As happened previously following the discovery of the cuprate superconductors, much effort has focused on determining whether this is a distinct, new type of superconducting state and what that might say about the superconducting mechanism. This talk will introduce two different spectroscopic techniques used to study the pairing state. Microwave superfluid density measurements on FeSe show the multiband nature of the superconducting state, as well as extreme gap anisotropy. Scanning tunnelling microscopy can provide even more information, by giving a means to measure the phase of the superconducting order parameter, as well as gap sizes. I will quasiparticle interference as the means to extract phase information, showing that LiFeAs is an s+- superconductor.
The University of Waterloo acknowledges that much of our work takes place on the traditional territory of the Neutral, Anishinaabeg and Haudenosaunee peoples. Our main campus is situated on the Haldimand Tract, the land granted to the Six Nations that includes six miles on each side of the Grand River. Our active work toward reconciliation takes place across our campuses through research, learning, teaching, and community building, and is centralized within our Indigenous Initiatives Office.