Edge Zeros and Boundary Spinons in Topological Mott Insulators

We investigate the role of Green’s function zeros in strongly interacting topological Mott insulators [1], focusing on their meaning and physical interpretation. Recent advancements, particularly through subsidiary rotor calculations of the Kane-Mele-Hubbard model, have established a connection between zeros and spinons and with U(1) gapped spin liquids [2,3]. We find a macroscopic spin-charge separation resulting from the non-trivial interplay with the conventional boundary modes of the topological insulator. We further employ our method to an attractive Hubbard-Haldane honeycomb model. In this context, the extensive slave-rotor mean-field calculations are used as a microscopic foundation to determine the phase diagram of the model as well as important phenomenological properties, such as the coherence length and penetration depth (Pearl length) within a topologically enabled mechanism of superconductivity.

[1] Wagner, N., Crippa, L., Amaricci, A. et al., Nat. Commun. 14, 7531 (2023)

[2] Wagner, N., Guerci, D., Millis, A. J. and Sangiovanni, G., Phys. Rev. Lett. 133, 126504 (2024)

[3] Bollmann, S., Setty, C., Seifert, U. F. P. and König, E. J., Phys. Rev. Lett. 133, 136504 (2024)