Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Enhanced multiexciton formation by an electron-hole plasma in 2D
  semiconductors   Multiexcitons in monolayer WSe2 exhibit a suite of optoelectronic phenomena
that are unique to those of their single exciton constituents. Here,
photoluminescence action spectroscopy shows that multiexciton formation is
enhanced with increasing optical excitation energy. This enhancement is
attributed to the multiexciton formation processes from an electron-hole plasma
and results in over 300% more multiexciton emission than at lower excitation
energies at 4 K. The energetic onset of the enhancement coincides with the
quasiparticle bandgap, corroborating the role of the electron-hole plasma, and
the enhancement diminishes with increasing temperature. The results reveal that
the strong interactions responsible for ultrafast exciton formation also affect
multiexciton phenomena, and both multiexciton and single exciton states play
significant roles in plasma thermalization in 2D semiconductors.

22
The categories of this paper are: chao-dyn
20
The categories of this paper are: acc-phys
34
The categories of this paper are: chem-ph
35
The categories of this paper are: mtrl-th
9
The categories of this paper are: nlin
5
The categories of this paper are: gr-qc
25
The categories of this paper are: patt-sol
17
The categories of this paper are: q-fin
13
The categories of this paper are: quant-ph
16
The categories of this paper are: stat
37
The categories of this paper are: supr-con
24
The categories of this paper are: dg-ga
36
The categories of this paper are: cmp-lg
3
The categories of this paper are: physics
11
The categories of this paper are: hep-lat
23
The categories of this paper are: solv-int