Nonuniform-flux saturation of the matching-point bound

Determine whether any nonuniform flux configuration at the matching point can simultaneously satisfy both equality conditions in the trace-norm and Lieb-theorem energy bounds.

Background

At the matching point, the authors derive a global lower bound on the unprojected Majorana energy by decomposing the hopping matrix into two uniform-magnitude honeycomb hopping matrices and applying the trace-norm triangle inequality together with Lieb’s theorem. The uniform flux-free sector is shown to saturate this bound, but the analysis does not determine whether another, nonuniform flux sector can also saturate both inequalities.

References

Whether any nonuniform flux configuration can satisfy both equality conditions is not established here.

— Exact selection of a toric-code vison crystal in a flux-conditioned Kitaev model  (2609.29004 - Wang et al., 24 Sep 2026) in Section 3.1, subsection “Complementary limit: the matching point”