  We perform an optical spectroscopy study to investigate the properties of
different artificial MoS$_2$ bi- and trilayer stacks created from individual
monolayers by a deterministic transfer process. These twisted bi- and trilayers
differ from the common 2H stacking in mineral MoS$_2$ in the relative stacking
angle of adjacent layers and the interlayer distance. The combination of Raman
spectroscopy, second-harmonic-generation microscopy and photoluminescence
measurements allows us to determine the degree of interlayer coupling in our
samples. We find that even for electronically decoupled artificial structures,
which show the same valley polarization degree as the constituent MoS$_2$
monolayers at low temperatures, there is a resonant energy transfer between
individual layers which acts as an effective luminescence quenching mechanism.
