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Toward Complete Characterization of Topological Insulators and Superconductors: A Systematic Construction of Topological Invariants Based on Atiyah-Hirzebruch Spectral Sequence

Seishiro Ono1,2,*,‡ and Ken Shiozaki3,†,‡

  • *Contact author: s-ono@g.ecc.u-tokyo.ac.jp
  • †Contact author: ken.shiozaki@yukawa.kyoto-u.ac.jp
  • ‡These authors contributed equally to this work.
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Phys. Rev. X 16, 041024 – Published 23 October, 2026

DOI: https://doi.org/10.1103/2rw7-bzl4

Abstract

The past decade has witnessed significant progress in topological materials investigation. Symmetry-indicator theory and topological quantum chemistry provide an efficient scheme to diagnose topological phases from only partial information of wave functions without full knowledge of topological invariants, which has resulted in a recent comprehensive materials search. However, not all topological phases can be captured by this framework, and topological invariants are needed for a more refined diagnosis of topological phases. In this study, we present a systematic framework to construct topological invariants for a large part of symmetry classes, which should be contrasted with the existing invariants discovered through one-by-one approaches. Our method is based on the recently developed Atiyah-Hirzebruch spectral sequence in momentum space. As a demonstration, we construct topological invariants for time-reversal-symmetric spinful superconductors with conventional pairing symmetries of all space groups, for which symmetry indicators are silent. We also validate that the obtained quantities work as topological invariants by computing them for randomly generated symmetric Hamiltonians. Remarkably, the constructed topological invariants completely characterize K groups in 159 space groups. Our topological invariants for normal conducting phases are defined under some gauge conditions. To facilitate efficient numerical simulations, we discuss how to derive gauge-independent topological invariants from the gauge-fixed topological invariants through some examples. Combined with first-principles calculations, our results will help us discover topological materials that could be used in next-generation devices and pave the way for a more comprehensive topological materials database.

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Popular Summary

Identifying the complete landscape of topological materials remains difficult because standard symmetry-based diagnosis misses many nontrivial electronic phases. We addressed this limitation by developing a systematic method to construct topological invariants using a framework based on the Atiyah-Hirzebruch spectral sequence in momentum space.

Applying our approach to time-reversal-symmetric spinful superconductors with conventional pairing symmetries, we obtained topological invariants that completely distinguish stable topological phases across 159 of the 230 spatial space groups. Our work provides a mathematical foundation to expand topological material databases, guiding the first-principles discovery of candidate materials for quantum computing and low-power electronic devices.

Article Text

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Phys. Rev. X 16, 041024– Published 23 October, 2026
  • Received 15 May 2026
  • Revised 30 July 2026
  • Accepted 4 August 2026
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