  The monolayers of semiconducting transition metal dichalcogenides host
strongly bound excitonic complexes and are an excellent platform for exploring
many-body physics. Here we demonstrate a controlled kinetic manipulation of the
five-particle excitonic complex, the charged biexciton, through a systematic
dependence of the biexciton peak on excitation power, gate voltage, and
temperature using steady-state and time-resolved photoluminescence (PL). With
the help of a combination of the experimental data and a rate equation model,
we argue that the binding energy of the charged biexciton is less than the
spectral separation of its peak from the neutral exciton. We also note that
while the momentum-direct radiative recombination of the neutral exciton is
restricted within the light cone, such restriction is relaxed for a charged
biexciton recombination due to the presence of near-parallel excited and final
states in the momentum space.
