  Beyond the conventional electron pairing mediated by phonons,
high-temperature superconductivity in cuprates is believed to stem from quantum
spin liquid (QSL). The unconventional superconductivity by doping a spin
liquid/Mott insulator, is a long-sought goal but a principal challenge in
condensed matter physics because of the lack of an ideal QSL platform. Here we
report the pressure induced metallization and possible unconventional
superconductivity in $NaYbSe_{2}$, which belongs to a large and ideal family of
triangular lattice spin liquid we revealed recently and is evidenced to possess
a QSL ground state. The charge gap of NaYbSe2 is gradually reduced by applying
pressures, and at ~20 GPa the crystal jumps into a superconducting (SC) phase
with Tc ~ 5.8 K even before the insulating gap is completely closed. The
metallization is confirmed by further high-pressure experiments but the sign of
superconductivity is not well repeated. No symmetry breaking accompanies the SC
transition, as indicated by X-ray diffraction and low-temperature Raman
experiments under high pressures. This intrinsically connects QSL and SC
phases, and suggests an unconventional superconductivity developed from QSL. We
further observed the magnetic-field-tuned superconductor-insulator transition
which is analogous to that found in the underdoped cuprate superconductor
$La_{2-x}Sr_{x}CuO_{4}$. The study is expected to inspire interest in exploring
new types of superconductors and sheds light into the intriguing physics from a
spin liquid/Mott insulator to a superconductor.
