  We report the observation of anomalous Hall resistivity in single crystals of
EuAl$_4$, a centrosymmetric tetragonal compound, which exhibits coexisting
antiferromagnetic (AFM) and charge-density-wave (CDW) orders with onset at
$T_\mathrm{N} \sim 15.6$ K and $T_\mathrm{CDW} \sim 140$ K, respectively. In
the AFM state, when the magnetic field is applied along the $c$-axis direction,
EuAl$_4$ undergoes a series of metamagnetic transitions. Within this field
range, we observe a clear hump-like anomaly in the Hall resistivity,
representing part of the anomalous Hall resistivity. By considering different
scenarios, we conclude that such a hump-like feature is most likely a
manifestation of the topological Hall effect, normally occurring in
noncentrosymmetric materials known to host nontrivial topological spin
textures. In view of this, EuAl$_4$ would represent a rare case where the
topological Hall effect not only arises in a centrosymmetric structure, but it
also coexists with CDW order.

Strongly Correlated Electrons;Materials Science