  Magnetic semimetals have increasingly emerged as lucrative platforms hosting
spin-based topological phenomena in real and momentum spaces. Of particular
interest is the emergence of Berry curvature, whose geometric origin,
accessibility from Hall transport experiments, and material tunability, bodes
well for new physics and practical devices. Cr1+dTe2, a self-intercalated
magnetic transition metal dichalcogenide, TMD, exhibits attractive natural
attributes relevant to such applications, including topological magnetism,
tunable electron filling, magnetic frustration etc. While recent studies have
explored real-space Berry curvature effects in this material, similar
considerations of momentum-space Berry curvature are lacking. Here, we
systematically investigate the electronic structure and transport properties of
epitaxial Cr1+dTe2 thin films over a wide range of doping, d between 0.33 and
0.71. Spectroscopic experiments reveal the presence of a characteristic
semi-metallic band region near the Brillouin Zone edge, which shows a rigid
band like energy shift as a function of d. Transport experiments show that the
intrinsic component of the anomalous Hall effect, AHE, is sizable, and
undergoes a sign flip across d. Finally, density functional theory calculations
establish a causal link between the observed doping evolution of the band
structure and AHE: the AHE sign flip is shown to emerge from the sign change of
the Berry curvature, as the semi-metallic band region crosses the Fermi energy.
Our findings underscore the increasing relevance of momentum-space Berry
curvature in magnetic TMDs and provide a unique platform for intertwining
topological physics in real and momentum spaces.
