  We present a search for magnetic monopoles and high-electric-charge objects
using LHC Run 2 $\sqrt{s} =$13 TeV proton$-$proton collisions recorded by the
ATLAS detector. A total integrated luminosity of 138 fb$^{-1}$ was collected by
a specialized trigger. No highly ionizing particle candidate was observed.
Considering the Drell-Yan and photon-fusion pair production mechanisms as
benchmark models, cross-section upper limits are presented for spin-0 and
spin-$\frac{1}{2}$ magnetic monopoles of magnetic charge $1g_\textrm{D}$ and
$2g_\textrm{D}$ and for high-electric-charge objects of electric charge $20
\leq |z| \leq 100$, for masses between 200 GeV and 4000 GeV. The search
improves by approximately a factor of three the previous cross-section limits
on the Drell-Yan production of magnetic monopoles and high-electric charge
objects. Also, the first ATLAS limits on the photon-fusion pair production
mechanism of magnetic monopoles and high-electric-charge objects have been
obtained.
