  The viability of past, current and future devices for information technology
hinges on their sensitivity to the presence of impurities. The latter can lead
to resistivity anomalies, the so-called Kondo effect, reshape extrinsically
Hall effects or reduce the efficiency of magnetoresistance effects essential in
spintronics. Here we demonstrate that atomic defects enable highly efficient
all-electrical detection of spin-swirling textures, in particular magnetic
skyrmions, which are promising bits candidates in future spintronics devices.
Impurities amplify the bare transport signal and can alter significantly the
spin-mixing magnetoresistance (XMR) depending on their chemical nature. Both
effects are monitored in terms of the defect-enhanced XMR (DXMR) as shown for
3d and 4d transition metal defects implanted at the vicinity of skyrmions
generated in PdFe bilayer deposited on Ir(111). The ineluctability of
impurities in devices promotes the implementation of DXMR in reading
architectures with immediate implications in magnetic storage technologies.
