  The linear positive magnetoresistance (LPMR) is a widely observed phenomenon
in topological materials, which is promising for potential applications on
topological spintronics. However, its mechanism remains ambiguous yet and the
effect is thus uncontrollable. Here, we report a quantitative scaling model
that correlates the LPMR with the Berry curvature, based on a ferromagnetic
Weyl semimetal CoS2 that bears the largest LPMR of over 500% at 2 Kelvin and 9
Tesla, among known magnetic topological semimetals. In this system, masses of
Weyl nodes existing near the Fermi level, revealed by theoretical calculations,
serve as Berry-curvature monopoles and low-effective-mass carriers. Based on
the Weyl picture, we propose a relation \[\text{MR}=\frac{e}{\hbar }B{{\Omega
}_{\text{F}}}\], with B being the applied magnetic field and \[{{\Omega
}_{\text{F}}}\] the average Berry curvature near the Fermi surface, and further
introduce temperature factor to both MR/B slope (MR per unit field) and
anomalous Hall conductivity, which establishes the connection between the model
and experimental measurements. A clear picture of the linearly slowing down of
carriers, i.e., the LPMR effect, is demonstrated under the cooperation of the
k-space Berry curvature and real-space magnetic field. Our study not only
provides an experimental evidence of Berry curvature induced LPMR for the first
time, but also promotes the common understanding and functional designing of
the large Berry-curvature MR in topological Dirac/Weyl systems for magnetic
sensing or information storage.
