This invention relates to a laser cavity with passive triggering by saturable absorbent and with controlled polarization, and to a laser and in particular to a microlaser containing the said cavity and means of pumping this cavity. The invention also relates to a process for manufacturing the said microlaser. The laser cavity with controlled polarization comprises a substrate made of Y₃Al₅O₁₂ (YAG) active laser material that may or may not be doped, on which a monocrystalline layer of saturable absorbent doped YAG material is deposited directly by liquid phase epitaxy or by a similar process, in which the said active laser material has a [100] orientation, and in which the said monocrystalline layer of saturable absorbent material is deposited with the same [100] orientation.