  Superconductivity in the type-II Weyl semimetal candidate MoTe$_2$ has
attracted much attention due to the possible realization of topological
superconductivity. Under applied pressure, the superconducting transition
temperature is significantly enhanced, while the structural transition from the
high-temperature 1$T'$ phase to the low-temperature $T_d$ phase is suppressed.
Hence, applying pressure allows us to investigate the dimensionality of
superconductivity in 1$T'$-MoTe$_2$. We have performed a detailed study of the
magnetotransport properties and upper critical field $H_{c2}$ of MoTe$_2$ under
pressure. The magnetoresistance (MR) and Hall coefficient of MoTe$_2$ are found
to be decreasing with increasing pressure. In addition, the Kohler's scalings
for the MR data above $\sim$11 kbar show a change of exponent whereas the data
at lower pressure can be well scaled with a single exponent. These results are
suggestive of a Fermi surface reconstruction when the structure changes from
the $T_d$ to 1$T'$ phase. The $H_{c2}$-temperature phase diagram constructed at
15 kbar, with $H\parallel ab$ and $H\perp ab$, can be satisfactorily described
by the Werthamer-Helfand-Hohenberg model with the Maki parameters $\alpha \sim$
0.77 and 0.45, respectively. The relatively large $\alpha$ may stem from a
small Fermi surface and a large effective mass of semimetallic MoTe$_2$. The
angular dependence of $H_{c2}$ at 15 kbar can be well fitted by the Tinkham
model, suggesting the two-dimensional nature of superconductivity in the
high-pressure 1$T'$ phase.
