Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Ground-state Properties of a Supersolid in RPA   We investigate the newly discovered supersolid phase by solving in
random-phase approximation the anisotropic Heisenberg model of the hard-core
boson ${}^4$He lattice at zero temperature. We include nearest and next-nearest
neighbor interactions and calculate exactly all pair correlation functions in a
cumulant decoupling scheme. We demonstrate the importance of vacancies and
interstitials in the formation of the supersolid phase. The supersolid phase is
characterised by strong quantum fluctuations which are taken into account
rigorously. Furthermore we confirm that the superfluid to supersolid transition
is triggered by a collapsing roton minimum however is stable against
spontaneously induced superflow, i.e. vortex creation.

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The categories of this paper are: hep-lat
27
The categories of this paper are: comp-gas
6
The categories of this paper are: astro-ph
35
The categories of this paper are: mtrl-th
20
The categories of this paper are: acc-phys
16
The categories of this paper are: stat
29
The categories of this paper are: funct-an
14
The categories of this paper are: math-ph
8
The categories of this paper are: hep-ex
5
The categories of this paper are: gr-qc
10
The categories of this paper are: q-bio
30
The categories of this paper are: q-alg
12
The categories of this paper are: nucl-th
26
The categories of this paper are: bayes-an
21
The categories of this paper are: adap-org
25
The categories of this paper are: patt-sol