Classifying phases of matter has entertained generations, using symmetry as the primary tool for their categorization. Often we consider local symmetries, such as spin or rotation symmetries, to define constant quantum numbers. In a crystalline environment, the lattice includes discrete translation symmetries whose intricate relation to local symmetries introduces new quantum numbers that describe how not a single electron state but an entire band transforms together - topological invariants.
Engineering phases with nontrivial topology are of significant interest for technologies and fundamental research. In this talk, I will discuss how we may use the lattice in unconventional ways to realize topological phases. Particularly, I will describe how we can utilize crystalline defects to construct one and two-dimensional topological phases that both harbor exotic electronic states at their boundaries and are characterized by quantized physical responses.
About the speaker
Raquel Queiroz is an Assistant Professor of Physics at Columbia University. Her group studies how the behavior of materials is determined by geometric properties of quantum states using computational and theoretical techniques and in close collaboration with experimentalists. She obtained her undergraduate degrees in Physics at the University of Lisbon, Instituto Superior Tecnico, in 2009; her M.A. at Imperial College London in 2010; and her Ph.D. at the Max Planck Institute for Solid State Research in 2015. Her postdoctoral work was at the Weizmann Institute of Science in Rehovot, Israel, where she received the Koshland and the Feinberg prizes for outstanding achievements.