  The large anomalous Hall effect (AHE) in antiferromagnetic (AF) materials
arises from symmetry breaking equivalent to a ferromagnetic (FM) state.
Consequently, this suggests that the observed AHE is induced by the intrinsic
mechanism of the band structure effect, which in turn induces dissipationless
transverse conductivity. Confirmation of impurity-insensitive anomalous Hall
conductivity (AHC) is crucial to conclude this interpretation; however,
experimental investigations in AF materials are limited by the lack of high
quality systems. In this study, we show that the AF material NbMnP, which
exhibits a large AHE, offers a high quality single crystal. Our findings
clearly revealed that the large AHC and the tiny net magnetization of
$\sim10^{-3} \mu_{\mathrm{B}}$/Mn are inherent in this material, irrespective
of disorder. NbMnP is a novel AF material that generates FM responses in the
regime where there is less impurity scattering.
