Schreiber QMATH16

A talk that I have given:

---

• Urs Schreiber$\;\;$ (on work at CQTS with H. Sati)

  
  

  Identifying Anyonic Topological Order in

  Fractional Quantum Anomalous Hall Systems

  • slides: pdf (overlay)

  • slides: pdf (static & abridged)

  • draft recording: yt

• talk at:

  QMATH16, Munich (1-5 Sept 2025)

---

Based on:

• Identifying Anyonic Topological Order in Fractional Quantum Anomalous Hall Systems

  [pdf, arXiv:2507.00138]

• FQH Liquids with Flux-Expulsion Islands allow Nonabelian Anyons

Abstract:

• Recently observed fractional quantum anomalous Hall materials (FQAH) are candidates for topological quantum hardware, but their required anyon states are elusive. We point out dependence on monodromy of the fragile band topology in 2-cohomotopy. An algebro-topological theorem of Larmore & Thomas (1980) then identifies FQAH anyons over momentum space. Admissible braiding phases are $2C$-th roots of unity, for $C$ the Chern number. This lays the foundation for understanding symmetry-protected topological order in FQAH systems, reducing the problem to computations in equivariant cohomotopy.

Slide show:

Related presentations:

• at ISQS29 (brief talk)

• at Bilkent25 (seminar talk)

• Rethinking Topological Quantum (lightning talk)

• Rethinking FQH Anyons (talk)

• Engineering of Anyons on M5-Probes (lecture series)

Featured at QuantumZeitgeist: