Robustness of sequential channel quenching under realistic perturbations

Quantify the extent to which sequential quenching of the inner and outer transport channels in a nodal-line semimetal magnetic barrier survives smooth barrier edges, disorder, and finite temperature, all of which are expected to soften the sharp transmission cutoffs.

Background

The paper analyzes an idealized magnetic barrier with abrupt step-profile edges, no disorder, and zero temperature. In this setting, the inner contour is completely suppressed at a lower field–width product than the outer contour, producing a channel-selective transport window and sharp conductance cutoffs.

The authors identify smooth edges, disorder, and finite temperature as realistic effects that can soften these cutoffs, but do not determine whether the sequential suppression of the two channels remains observable or how strongly it is modified. Quantifying this robustness is therefore necessary for assessing the viability of the proposed transport signature in experiments.