  Excitonic quasi-particles, excitons/trions/bi-excitons, and their coupling
with phonons and charge carriers play a crucial role in controlling the optical
properties of atomically thin semiconducting 2D materials. In this work, we
unravelled the dynamics of excitons/trions and their coupling with phonons and
charge carriers in a few layers vertically and horizontally aligned MoS2. We
observed trion signature up to the highest recorded temperature (330 K) in both
systems and have shown that the dynamics of excitons/trions and their coupling
with phonons and electrons are more affected in vertically aligned MoS2. A
homogeneous linewidth broadening is observed with an increase in temperature.
The linewidth broadening is attributed mainly to acoustic phonons in a
low-temperature regime (<100 K). In contrast, acoustic and longitudinal optical
phonons contributions to the linewidth broadening are observed at high
temperature. We also observed the significant effects of interlayer coupling in
both systems via understanding the temperature-dependent valence band splitting
and trion binding energy. A decrease of 22 and 12% in valence band splitting
with temperature rise is observed for the vertically and horizontally aligned
MoS2, respectively, suggesting that the valence band splitting is affected more
in the case of vertically than horizontally aligned. Furthermore, we also
notice a significant thermal quenching in the intensity of the trion band than
that of exciton bands, attributed to the small binding energy of the trion.
