Interaction-induced sign reversal of the orbital magnetic susceptibility in Chern insulators
Abstract
It has been well established that the orbital magnetization of interacting electrons can be simply evaluated by applying the single-particle formula to self-consistent HF bands. However, we show that such procedure fails qualitatively for orbital magnetic susceptibility, especially in topological systems: in a Chern-insulating phase of twisted MoTe2, the interaction-induced correction reverses the sign of the susceptibility. This result follows from an algebraic framework that solves the HF problem at finite magnetic field, where noncommuting canonical momenta obstruct a direct calculation: a \emph{reverse Peierls substitution} maps every magnetic-translation-invariant operator to a unique bivariate function, converting the finite-field self-consistency into a function equation that can be expanded systematically in B. At first order, this yields a linear equation for the field-induced change δX of the Fock potential, leading to an intrinsically interaction-induced susceptibility in addition to a single-particle-like one. The framework reproduces the Středa formula for insulators, and an auxiliary-Hilbert-space construction carries it to periodic and moiré systems. Finite-field HF calculations in a gapped Dirac model and in the twisted-MoTe2 Chern insulator confirm the theory quantitatively.
Versions
Related
- Magnetic-field-induced corner states in quantum spin Hall insulators
- Quantum Landau Lifshitz Gilbert equation in ferromagnetic conductors and magnetic insulators
- Magnetic enhancement and Hall conductivity of excitonic insulators in a Gross--Neveu type model
- Three-dimensional quantum Hall insulators in magnetic pyrochlore systems
- Nonlinearity-Induced Suppression of Dissipation in Bath-Coupled Floquet Topological Insulators
BibTeX
@misc{huang2026interactioninduced,
title = {{Interaction-induced sign reversal of the orbital magnetic susceptibility in Chern insulators}},
author = {Ke Huang and Xiao Li},
howpublished = {arXiv},
year = {2026},
month = aug,
doi = {10.48550/arxiv.2607.27112},
eprint = {2607.27112},
archivePrefix = {arXiv},
url = {https://arxiv.org/abs/2607.27112},
}
RIS
TY - UNPB
TI - Interaction-induced sign reversal of the orbital magnetic susceptibility in Chern insulators
AU - Ke Huang
AU - Xiao Li
PY - 2026
DA - 2026/08/09
PB - arXiv
DO - 10.48550/arxiv.2607.27112
UR - https://arxiv.org/abs/2607.27112
AB - It has been well established that the orbital magnetization of interacting electrons can be simply evaluated by applying the single-particle formula to self-consistent HF bands. However, we show that such procedure fails qualitatively for orbital magnetic susceptibility, especially in topological systems: in a Chern-insulating phase of twisted MoTe_2, the interaction-induced correction reverses the sign of the susceptibility. This result follows from an algebraic framework that solves the HF problem at finite magnetic field, where noncommuting canonical momenta obstruct a direct calculation: a \emph{reverse Peierls substitution} maps every magnetic-translation-invariant operator to a unique bivariate function, converting the finite-field self-consistency into a function equation that can be expanded systematically in B. At first order, this yields a linear equation for the field-induced change δX of the Fock potential, leading to an intrinsically interaction-induced susceptibility in addition to a single-particle-like one. The framework reproduces the Středa formula for insulators, and an auxiliary-Hilbert-space construction carries it to periodic and moiré systems. Finite-field HF calculations in a gapped Dirac model and in the twisted-MoTe_2 Chern insulator confirm the theory quantitatively.
ER -