- Open Access
Charge pumps, pivot Hamiltonians, and symmetry-protected topological phases
Phys. Rev. B 112, 165123 – Published 15 October, 2025
DOI: https://doi.org/10.1103/rtq1-pplf
Abstract
Generalized charge pumps are topological obstructions to trivializing loops in the space of symmetric gapped Hamiltonians. We show that given mild conditions on such pumps, the associated loop has high-symmetry points that must be in distinct symmetry-protected topological (SPT) phases. To further elucidate the connection between pumps and SPTs, we focus on closed paths, “pivot loops”, defined by two Hamiltonians, where the first is unitarily evolved by the second “pivot” Hamiltonian. While such pivot loops have been studied as entanglers for SPTs, here we explore their connection to pumps. We construct families of pivot loops that pump charge for various symmetry groups, often leading to SPT phases—including dipole SPTs. Intriguingly, we find examples where nontrivial pumps do not lead to genuine SPTs but still entangle representation-SPTs (RSPTs). We use the anomaly associated with the nontrivial pump to explain the a priori “unnecessary” criticality between these RSPTs. We also find that particularly nice pivot families form circles in Hamiltonian space, which we show are equivalent to the Hamiltonians satisfying the Dolan-Grady relation—known from the study of integrable models. This additional structure allows us to derive more powerful constraints on the phase diagram. Natural examples of such circular loops arise from pivoting with the Onsager-integrable chiral clock models, containing the aforementioned RSPT example. In fact, we show that these Onsager pivots underlie general group cohomology-based pumps in one spatial dimension. Finally, we recast the above in the language of equivariant families of Hamiltonians and relate the invariants of the pump to the candidate SPTs. We also highlight how certain SPTs arise in cases where the equivariant family is labeled by spaces that are not manifolds.
Physics Subject Headings (PhySH)
Article Text
References (102)
- D. J. Thouless, Quantization of particle transport, Phys. Rev. B 27, 6083 (1983).
- P.-S. Hsin, A. Kapustin, and R. Thorngren, Berry phase in quantum field theory: Diabolical points and boundary phenomena, Phys. Rev. B 102, 245113 (2020).
- C. Córdova, D. S. Freed, H. T. Lam, and N. Seiberg, Anomalies in the space of coupling constants and their dynamical applications I, SciPost Phys. 8, 001 (2020).
- M. Hermele, Families of gapped systems and quantum pumps, Talk at Harvard CMSA (2021), https://www.youtube.com/watch?v=wtaC0tqXZMU.
- K. Shiozaki, Adiabatic cycles of quantum spin systems, Phys. Rev. B 106, 125108 (2022).
- X. Wen, M. Qi, A. Beaudry, J. Moreno, M. J. Pflaum, D. Spiegel, A. Vishwanath, and M. Hermele, Flow of higher Berry curvature and bulk-boundary correspondence in parametrized quantum systems, Phys. Rev. B 108, 125147 (2023).
- A. Kitaev, On the classification of Short-Range Entangled states, Talk at Simons Center for Geometry and Physics (2013), scgp.stonybrook.edu/archives/7874.
- D. Gaiotto and T. Johnson-Freyd, Symmetry protected topological phases and generalized cohomology, J. High Energy Phys. 05 (2019) 007.
- A. Debray, S. K. Devalapurkar, C. Krulewski, Y. L. Liu, N. Pacheco-Tallaj, and R. Thorngren, A long exact sequence in symmetry breaking: Order parameter constraints, defect anomaly-matching, and higher Berry phases, J. High Energy Phys. 07 (2025) 007.
- N. Tantivasadakarn, R. Thorngren, A. Vishwanath, and R. Verresen, Pivot Hamiltonians as generators of symmetry and entanglement, SciPost Phys. 14, 012 (2023).
- N. Tantivasadakarn, R. Thorngren, A. Vishwanath, and R. Verresen, Building models of topological quantum criticality from pivot Hamiltonians, SciPost Phys. 14, 013 (2023).
- N. G. Jones, A. Prakash, and P. Fendley, Pivoting through the chiral-clock family, SciPost Phys. 18, 094 (2025).
- Z.-C. Gu and X.-G. Wen, Tensor-entanglement-filtering renormalization approach and symmetry-protected topological order, Phys. Rev. B 80, 155131 (2009).
- F. Pollmann, A. M. Turner, E. Berg, and M. Oshikawa, Entanglement spectrum of a topological phase in one dimension, Phys. Rev. B 81, 064439 (2010).
- L. Fidkowski and A. Kitaev, Effects of interactions on the topological classification of free fermion systems, Phys. Rev. B 81, 134509 (2010).
- A. M. Turner, F. Pollmann, and E. Berg, Topological phases of one-dimensional fermions: An entanglement point of view, Phys. Rev. B 83, 075102 (2011).
- N. Schuch, D. Pérez-García, and I. Cirac, Classifying quantum phases using matrix product states and projected entangled pair states, Phys. Rev. B 84, 165139 (2011).
- X. Chen, Z.-C. Gu, and X.-G. Wen, Classification of gapped symmetric phases in one-dimensional spin systems, Phys. Rev. B 83, 035107 (2011).
- F. Pollmann and A. M. Turner, Detection of symmetry-protected topological phases in one dimension, Phys. Rev. B 86, 125441 (2012).
- T. Senthil, Symmetry-protected topological phases of quantum matter, Annu. Rev. Condens. Matter Phys. 6, 299 (2015).
- R. Verresen, R. Moessner, and F. Pollmann, One-dimensional symmetry protected topological phases and their transitions, Phys. Rev. B 96, 165124 (2017).
- X. Chen, Y.-M. Lu, and A. Vishwanath, Symmetry-protected topological phases from decorated domain walls, Nat. Commun. 5, 3507 (2014).
- R. Verresen, R. Thorngren, N. G. Jones, and F. Pollmann, Gapless topological phases and symmetry-enriched quantum criticality, Phys. Rev. X 11, 041059 (2021).
- C. Zhang, Topological invariants for symmetry-protected topological phase entanglers, Phys. Rev. B 107, 235104 (2023).
- H. J. Briegel and R. Raussendorf, Persistent entanglement in arrays of interacting particles, Phys. Rev. Lett. 86, 910 (2001).
- W. Son, L. Amico, R. Fazio, A. Hamma, S. Pascazio, and V. Vedral, Quantum phase transition between cluster and antiferromagnetic states, Europhys. Lett. 95, 50001 (2011).
- M. Levin and Z.-C. Gu, Braiding statistics approach to symmetry-protected topological phases, Phys. Rev. B 86, 115109 (2012).
- N. Bultinck, UV perspective on mixed anomalies at critical points between bosonic symmetry-protected phases, Phys. Rev. B 100, 165132 (2019).
- L. Onsager, Crystal statistics. I. A two-dimensional model with an order-disorder transition, Phys. Rev. 65, 117 (1944).
- Indeed, it reduces to for . Note that this is not the cluster model that we discuss in Sec. 7 below [82, 83].
- E. O'Brien, E. Vernier, and P. Fendley, “Not-”, representation symmetry-protected topological, and Potts phases in an -invariant chain, Phys. Rev. B 101, 235108 (2020).
- R. Verresen, P. Fendley, and N. Tantivasadakarn (unpublished).
- A. Kitaev, Toward a topological classification of many- body quantum states with short-range entanglement, Talk at Simons Center for Geometry and Physics (2011), https://scgp.stonybrook.edu/archives/1087.
- Although we will not require a concrete definition, in the broadest sense of the term these are also called invertible states, for each such state there is a corresponding state that tensors to give the trivial phase [93]. Their appearance is natural as we expect a pump to be reversible.
- Such a loop is a family of Hamiltonians parameterized by a circle. One can further generalise to families parameterized by other spaces [6], see also Sec. 10.
- K. Inamura and S. Ohyama, 1+1d SPT phases with fusion category symmetry: interface modes and non-Abelian Thouless pump, arXiv:2408.15960.
- Strictly speaking, this result is for compact symmetry groups —we will focus on finite symmetry groups in this work.
- S. Bachmann, W. De Roeck, M. Fraas, and T. Jappens, A classification of G-charge Thouless pumps in 1D invertible states, Commun. Math. Phys. 405, 157 (2024).
- W. Magnus, On the exponential solution of differential equations for a linear operator, Commun. Pure Appl. Math. 7, 649 (1954).
- This is a different notion of generalized symmetries to that found in Ref. [102].
- J. Naudts, T. Verhulst, and B. Anthonis, Counting operator analysis of the discrete spectrum of some model Hamiltonians, Phys. Lett. A 373, 3419 (2009).
- J. Naudts and T. Verhulst, A multiplet analysis of spectra in the presence of broken symmetries, J. Phys.: Conf. Ser. 343, 012084 (2012).
- This is not necessarily the case (we could have an symmetry), but all examples we are aware of give rise to a symmetry on rescaling.
- B. Davies, Onsager's algebra and superintegrability, J. Phys. A: Math. Gen. 23, 2245 (1990).
- D. V. Else and C. Nayak, Classifying symmetry-protected topological phases through the anomalous action of the symmetry on the edge, Phys. Rev. B 90, 235137 (2014).
- A. Kapustin and N. Sopenko, Anomalous symmetries of quantum spin chains and a generalization of the Lieb-Schultz-Mattis theorem, Commun. Math. Phys. 406, 238 (2025).
- X. Chen, Z.-C. Gu, Z.-X. Liu, and X.-G. Wen, Symmetry protected topological orders and the group cohomology of their symmetry group, Phys. Rev. B 87, 155114 (2013).
- O. Buerschaper, Twisted injectivity in projected entangled pair states and the classification of quantum phases, Ann. Phys. 351, 447 (2014).
- R. Roy and F. Harper, Floquet topological phases with symmetry in all dimensions, Phys. Rev. B 95, 195128 (2017).
- The key general notions are that the invariant is additive if we encircle two diabolical points, and that applying that commutes with does not change the value of the invariant.
- B. Zeng, X. Chen, D.-L. Zhou, and X.-G. Wen, Quantum Information Meets Quantum Matter (Springer, New York, 2019).
- J. I. Cirac, D. Pérez-García, N. Schuch, and F. Verstraete, Matrix product states and projected entangled pair states: Concepts, symmetries, theorems, Rev. Mod. Phys. 93, 045003 (2021).
- Y. Kuno and Y. Hatsugai, Interaction-induced topological charge pump, Phys. Rev. Res. 2, 042024(R) (2020).
- Note that for any path of gapped local Hamiltonians, one can use the quasi-adiabatic continuation to find a local unitary evolution acting on the ground state; and for a -symmetric path, the corresponding generating Hamiltonian can always be chosen -symmetric [38, 51].
- This means that we can write this operator as a tensor network with finite bond dimension. All of our pivot Hamiltonian examples are of this form, since they have commuting local terms.
- M. B. Şahinoğlu, S. K. Shukla, F. Bi, and X. Chen, Matrix product representation of locality preserving unitaries, Phys. Rev. B 98, 245122 (2018).
- M. B. Hastings, An area law for one-dimensional quantum systems, J. Stat. Mech.: Theory Exp. (2007) P08024.
- S. Ohyama and S. Ryu, Higher structures in matrix product states, Phys. Rev. B 109, 115152 (2024).
- M. Qi, D. T. Stephen, X. Wen, D. Spiegel, M. J. Pflaum, A. Beaudry, and M. Hermele, Charting the space of ground states with tensor networks, SciPost Phys. 18, 168 (2025).
- A technical condition that we can read as excluding symmetry breaking. See [52] for more details.
- C. W. von Keyserlingk and S. L. Sondhi, Phase structure of one-dimensional interacting Floquet systems. I. Abelian symmetry-protected topological phases, Phys. Rev. B 93, 245145 (2016).
- D. V. Else and C. Nayak, Classification of topological phases in periodically driven interacting systems, Phys. Rev. B 93, 201103(R) (2016).
- A. C. Potter and T. Morimoto, Dynamically enriched topological orders in driven two-dimensional systems, Phys. Rev. B 95, 155126 (2017).
- L. Dolan and M. Grady, Conserved charges from self-duality, Phys. Rev. D 25, 1587 (1982).
- J. H. H. Perk, Star-triangle equations, quantum Lax pairs, and higher genus curves, Theta Functions–Bowdoin 1987 49, 341 (1989).
- B. Davies, Onsager's algebra and the Dolan–Grady condition in the non-self-dual case, J. Math. Phys. 32, 2945 (1991).
- J. H. H. Perk, The early history of the integrable chiral Potts model and the odd–even problem, J. Phys. A: Math. Theor. 49, 153001 (2016).
- B. Davies, A twist on chiral Potts, J. Stat. Phys. 62, 89 (1991).
- C. Ahn and K. Shigemoto, Onsager algebra and integrable lattice models, Mod. Phys. Lett. A 06, 3509 (1991).
- E. Vernier, E. O'Brien, and P. Fendley, Onsager symmetries in U(1)-invariant clock models, J. Stat. Mech.: Theory Exp. (2019) 043107.
- N. D. Mermin and H. Wagner, Absence of Ferromagnetism or antiferromagnetism in one- or two-dimensional isotropic Heisenberg models, Phys. Rev. Lett. 17, 1133 (1966).
- P. C. Hohenberg, Existence of long-range order in one and two dimensions, Phys. Rev. 158, 383 (1967).
- S. Coleman, There are no Goldstone bosons in two dimensions, Commun. Math. Phys. 31, 259 (1973).
- M. Suzuki, Relationship among exactly soluble models of critical phenomena. I. 2D Ising model, dimer problem and the generalized XY-model, Prog. Theor. Phys. 46, 1337 (1971).
- Y. Kikuchi and Y. Tanizaki, Global inconsistency,'t Hooft anomaly, and level crossing in quantum mechanics, Prog. Theor. Exp. Phys. 2017, 113B05 (2017).
- D. Gaiotto, A. Kapustin, Z. Komargodski, and N. Seiberg, Theta, time reversal and temperature, J. High Energy Phys. 05 (2017) 091.
- C. Cordova, D. Freed, H. T. Lam, and N. Seiberg, Anomalies in the space of coupling constants and their dynamical applications II, SciPost Phys. 8, 002 (2020).
- Y. Kuno and Y. Hatsugai, Topological domain-wall pump with spontaneous symmetry breaking, Phys. Rev. Lett. 134, 226603 (2025).
- A. Kapustin, Symmetry protected topological phases, anomalies, and cobordisms: Beyond group cohomology, arXiv:1403.1467.
- Since we have . Since we chose the range , we have .
- G. von Gehlen and V. Rittenberg, ) symmetric quantum chains with an infinite set of conserved charges and ) zero modes, Nucl. Phys. B 257, 351 (1985).
- S. D. Geraedts and O. I. Motrunich, Exact models for symmetry-protected topological phases in one dimension, arXiv:1410.1580.
- L. H. Santos, Rokhsar-Kivelson models of bosonic symmetry-protected topological states, Phys. Rev. B 91, 155150 (2015).
- J. H. Han, E. Lake, H. T. Lam, R. Verresen, and Y. You, Topological quantum chains protected by dipolar and other modulated symmetries, Phys. Rev. B 109, 125121 (2024).
- P. Smacchia, L. Amico, P. Facchi, R. Fazio, G. Florio, S. Pascazio, and V. Vedral, Statistical mechanics of the cluster Ising model, Phys. Rev. A 84, 022304 (2011).
- L. Tsui, Y.-T. Huang, H.-C. Jiang, and D.-H. Lee, The phase transitions between bosonic topological phases in 1+1D, and a constraint on the central charge for the critical points between bosonic symmetry protected topological phases, Nucl. Phys. B 919, 470 (2017).
- N. Tantivasadakarn and A. Vishwanath, Symmetric finite-time preparation of cluster states via quantum pumps, Phys. Rev. Lett. 129, 090501 (2022).
- A. Prakash and S. A. Parameswaran, Charge pumps, boundary modes, and the necessity of unnecessary criticality, arXiv:2408.15351.
- This in fact holds for generalized cohomology theories, so these arguments apply to fermions/spin cobordism, theory, etc.).
- I. Hason, Z. Komargodski, and R. Thorngren, Anomaly matching in the symmetry broken phase: Domain walls, CPT, and the Smith isomorphism, SciPost Phys. 8, 062 (2020).
- It was shown in Ref. [9] that the ambiguity in , given , is given by tensoring with an anomaly free -equivariant family. Our equivalence relation on families does not allow this, so is an invariant.
- Since denotes the anomaly free subgroup, we denote Hamiltonians by in this section.
- A. Kapustin, N. Sopenko, and B. Yang, A classification of invertible phases of bosonic quantum lattice systems in one dimension, J. Math. Phys. 62, 081901 (2021).
- Y. Ogata, A classification of pure states on quantum spin chains satisfying the split property with on-site finite group symmetries, Trans. Am. Math. Soc. B 8, 39 (2021).
- T. Matsui, Boundedness of entanglement entropy and split property of quantum spin chains, Rev. Math. Phys. 25, 1350017 (2013).
- H. Widom, Asymptotic behavior of block Toeplitz matrices and determinants, Adv. Math. 13, 284 (1974).
- E. Basor, J. Dubail, T. Emig, and R. Santachiara, Modified Szegö–Widom asymptotics for block Toeplitz matrices with zero modes, J. Stat. Phys. 174, 28 (2019).
- N. G. Jones, R. Thorngren, and R. Verresen, Bulk-boundary correspondence and singularity-filling in long-range free-fermion chains, Phys. Rev. Lett. 130, 246601 (2023).
- A. Alase, E. Cobanera, G. Ortiz, and L. Viola, Wiener–Hopf factorization approach to a bulk-boundary correspondence and stability conditions for topological zero-energy modes, Ann. Phys. 458, 169457 (2023).
- S. Ohyama, K. Shiozaki, and M. Sato, Generalized Thouless pumps in -dimensional interacting fermionic systems, Phys. Rev. B 106, 165115 (2022).
- This can be further generalized, e.g., to include anti-unitary and spatial symmetries as well. We will not consider these for simplicity.
- D. Gaiotto, A. Kapustin, N. Seiberg, and B. Willett, Generalized global symmetries, J. High Energy Phys. 02 (2015) 172.