Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Exciton interaction induced spin splitting in MoS$_2$ monolayer   By pumping nonresonantly a MoS$_2$ monolayer at $13$ K under a circularly
polarized cw laser, we observe exciton energy redshifts that break the
degeneracy between B excitons with opposite spin. The energy splitting
increases monotonically with the laser power reaching as much as $18$ meV,
while it diminishes with the temperature. The phenomenon can be explained
theoretically by considering simultaneously the bandgap renormalization which
gives rise to the redshift and exciton-exciton Coulomb exchange interaction
which is responsible for the spin-dependent splitting. Our results offer a
simple scheme to control the valley degree of freedom in MoS$_2$ monolayer and
provide an accessible method in investigating many-body exciton exciton
interaction in such materials.

14
The categories of this paper are: math-ph
20
The categories of this paper are: acc-phys
15
The categories of this paper are: nucl-ex
12
The categories of this paper are: nucl-th
11
The categories of this paper are: hep-lat
16
The categories of this paper are: stat
0
The categories of this paper are: hep-ph
13
The categories of this paper are: quant-ph
23
The categories of this paper are: solv-int
10
The categories of this paper are: q-bio
21
The categories of this paper are: adap-org
7
The categories of this paper are: hep-th
1
The categories of this paper are: cs
36
The categories of this paper are: cmp-lg
5
The categories of this paper are: gr-qc
3
The categories of this paper are: physics