Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Exciton correlations and input-output relations in non-equilibrium
  exciton superfluids   The Photoluminescent (PL) measurements on photons and the transport
measurements on excitons are the two types of independent and complementary
detection tools to search for possible exciton superfluids in electron-hole
semi-conductor bilayer systems. In fact, it was believed that the transport
measurements can provide more direct evidences on superfluids than the
spectroscopic measurements. It is important to establish the relations between
the two kinds of measurements.
  In this paper, using quantum Heisenberg-Langevin equations, we establish such
a connection by calculating various exciton correlation functions in the
putative exciton superfluids. These correlation functions include both normal
and anomalous
  Greater, Lesser, Advanced, Retarded, and Time-ordered exciton Green functions
and also various two exciton correlation functions.
  We also evaluate the corresponding normal and anomalous spectral weights and
the Keldysh distribution functions.
  We stress the violations of the fluctuation and dissipation theorem among
these various exciton correlation functions in the non-equilibrium exciton
superfluids. We also explore the input-output relations between various exciton
correlation functions and those of emitted photons such as the angle resolved
photon power spectrum, phase sensitive two mode squeezing spectrum and two
photon correlations. Applications to possible superfluids in the
exciton-polariton systems are also mentioned.
  For a comparison, using conventional imaginary time formalism, we also
calculate all the exciton correlation functions in an equilibrium dissipative
exciton superfluid in the electron-electron coupled semi-conductor bilayers at
the quantum Hall regime at the total filling factor $ \nu_T= 1 $. We stress the
analogies and also important differences between the correlations functions in
the two exciton superfluid systems.

11
The categories of this paper are: hep-lat
32
The categories of this paper are: atom-ph
37
The categories of this paper are: supr-con
22
The categories of this paper are: chao-dyn
29
The categories of this paper are: funct-an
14
The categories of this paper are: math-ph
1
The categories of this paper are: cs
7
The categories of this paper are: hep-th
19
The categories of this paper are: eess
13
The categories of this paper are: quant-ph
9
The categories of this paper are: nlin
21
The categories of this paper are: adap-org
28
The categories of this paper are: alg-geom
30
The categories of this paper are: q-alg
8
The categories of this paper are: hep-ex
15
The categories of this paper are: nucl-ex