A quantum solvent is essentially a superfluid (aka a quantum liquid) used to dissolve another chemical species. Any superfluid can theoretically act as a quantum solvent, but in practice the only viable superfluid medium that can currently be used is helium-4, and it has been successfully accomplished in controlled conditions. Such solvents are currently under investigation for use in spectroscopic techniques in the field of analytical chemistry, due to their superior kinetic properties.