Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Excitons and biexcitons in symmetric electron-hole bilayers   Symmetric electron-hole bilayer systems have been studied at zero temperature
using the diffusion quantum Monte Carlo method. A flexible trial wave function
is used that can describe fluid, excitonic and biexcitonic phases. We calculate
condensate fractions and pair correlation functions for a large number of
densities rs and layer separations d. At small d we find a one-component fluid
phase, an excitonic fluid phase, and a biexcitonic fluid phase, and the
transitions among them appear to be continuous. At d = 0, excitons appear to
survive down to about rs = 0.5 a.u., and biexcitons form at rs > 2.5 a.u.

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The categories of this paper are: comp-gas
9
The categories of this paper are: nlin
29
The categories of this paper are: funct-an
7
The categories of this paper are: hep-th
14
The categories of this paper are: math-ph
26
The categories of this paper are: bayes-an
25
The categories of this paper are: patt-sol
34
The categories of this paper are: chem-ph
32
The categories of this paper are: atom-ph
15
The categories of this paper are: nucl-ex
13
The categories of this paper are: quant-ph
18
The categories of this paper are: econ
21
The categories of this paper are: adap-org
11
The categories of this paper are: hep-lat
8
The categories of this paper are: hep-ex
28
The categories of this paper are: alg-geom