  The discovery of intrinsic magnetism in atomically thin two-dimensional
transition-metal trichalcogenides has attracted intense research interest due
to the exotic properties of magnetism and potential applications in devices.
Pressure has proven to be an effective tool to manipulate the crystal and
electronic structures of the materials. Here, we report investigations on
ferromagnetic van der Waals Cr2Si2Te6 via high-pressure synchrotron x-ray
diffraction, electrical resistance, Hall resistance, and magnetoresistance
measurements. Under compression, Cr2Si2Te6 simultaneously undergoes a
structural transition, emergence of superconductivity at 3 K, sign change of
the magnetoresistance, and dramatic change of the Hall coefficient at ~8 GPa.
The superconductivity persists up to the highest measured pressure of 47.1 GPa
with a maximum Tc = 4.5 K at ~30 GPa. The discovery of superconductivity in the
two-dimensional van der Waals ferromagnetic Cr-based Cr2Si2Te6 provides new
perspectives to explore superconductivity and the interplay between
superconductivity and magnetism.
