Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Polaritons in an electron gas -- quasiparticles and Landau effective
  interactions   Two-dimensional semiconductors inside optical microcavities have emerged as a
versatile platform to explore new hybrid light-matter quantum states. The
strong light-matter coupling leads to the formation of exciton-polaritons,
which in turn interact with the surrounding electron gas to form quasiparticles
called polaron-polaritons. Here, we develop a general microscopic framework to
calculate the properties of these quasiparticles such as their energy and the
interactions between them. From this, we give microscopic expressions for the
parameters entering a Landau theory for the polaron-polaritons, which offers a
simple yet powerful way to describe such interacting light-matter many-body
systems. As an example of the application of our framework, we then use the
ladder approximation to explore the properties of the polaron-polaritons. We
furthermore show that they can be measured in a non-demolition way via the
light transmission/reflection spectrum of the system. Finally, we demonstrate
that the Landau effective interaction mediated by electron-hole excitation is
attractive leading to red shifts of the polaron-polaritons. Our work provides a
systematic framework to study exciton-polaritons in electronically doped
two-dimensional materials such as novel van der Waals heterostructures.

17
The categories of this paper are: q-fin
31
The categories of this paper are: ao-sci
19
The categories of this paper are: eess
22
The categories of this paper are: chao-dyn
36
The categories of this paper are: cmp-lg
18
The categories of this paper are: econ
26
The categories of this paper are: bayes-an
24
The categories of this paper are: dg-ga
3
The categories of this paper are: physics
30
The categories of this paper are: q-alg
7
The categories of this paper are: hep-th
12
The categories of this paper are: nucl-th
29
The categories of this paper are: funct-an
15
The categories of this paper are: nucl-ex
21
The categories of this paper are: adap-org
13
The categories of this paper are: quant-ph