Intrinsically gapless symmetryprotected topology
APA
Potter, A. (2022). Intrinsically gapless symmetryprotected topology. Perimeter Institute. https://pirsa.org/22110075
MLA
Potter, Andrew. Intrinsically gapless symmetryprotected topology. Perimeter Institute, Nov. 16, 2022, https://pirsa.org/22110075
BibTex
@misc{ pirsa_PIRSA:22110075, doi = {10.48660/22110075}, url = {https://pirsa.org/22110075}, author = {Potter, Andrew}, keywords = {Condensed Matter}, language = {en}, title = {Intrinsically gapless symmetryprotected topology}, publisher = {Perimeter Institute}, year = {2022}, month = {nov}, note = {PIRSA:22110075 see, \url{https://pirsa.org}} }

University of British Columbia
 Andrew Potter
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Talk Type
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Abstract
While sharplyquantized topological features are conventionally associated with gapped phases of matter, there are a growing number of examples of gapless systems with topologically protected edge states. A particularly striking set of examples are "intrinsically gapless" symmetryprotected topological states (igSPTs), which host topological surface states that could not arise in a gapped system with the same symmetries. Examples include familiar noninteracting Weyl semimetals with Fermi arc surface states, as well as more exotic examples like deconfined quantum critical points with topological edge states. In this talk, I will discuss recent progress in formally understanding the bulkboundary correspondence of stronglyinteracting igSPTs using tools from group cohomology. In these examples, the gaplessness of the bulk and presence of topological surface states can be understood in a unified way due to the presence of an emergent anomaly. Our formalism allows construction of latticemodels with such emergent anomalies whose topological properties can be deduced exactly.