  One of the most striking features of novel 2D semiconductors (e.g.,
transition metal dichalcogenide monolayers or phosphorene) is a strong Coulomb
interaction between charge carriers resulting in large excitonic effects. In
particular, this leads to the formation of multi-carrier bound states upon
photoexcitation (e.g., excitons, trions and biexcitons), which could remain
stable at near-room temperatures and contribute significantly to optical
properties of such materials. In the present work we have used the Path
Integral Monte Carlo methodology to numerically study properties of
multi-carrier bound states in 2D semiconductors. Specifically, we have
accurately investigated and tabulated the dependence of single exciton, trion
and biexciton binding energies on the strength of dielectric screening,
including the limiting cases of very strong and very weak screening. The
results of this work are potentially useful in the analysis of experimental
data and benchmarking of theoretical and computational models.
