Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Quantum Correlations in Two-Fermion Systems   We characterize and classify quantum correlations in two-fermion systems
having 2K single-particle states. For pure states we introduce the Slater
decomposition and rank (in analogy to Schmidt decomposition and rank), i.e. we
decompose the state into a combination of elementary Slater determinants formed
by mutually orthogonal single-particle states. Mixed states can be
characterized by their Slater number which is the minimal Slater rank required
to generate them. For K=2 we give a necessary and sufficient condition for a
state to have a Slater number of 1. We introduce a correlation measure for
mixed states which can be evaluated analytically for K=2. For higher K, we
provide a method of constructing and optimizing Slater number witnesses, i.e.
operators that detect Slater number for some states.

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The categories of this paper are: cs
31
The categories of this paper are: ao-sci
20
The categories of this paper are: acc-phys
15
The categories of this paper are: nucl-ex
37
The categories of this paper are: supr-con
24
The categories of this paper are: dg-ga
36
The categories of this paper are: cmp-lg
27
The categories of this paper are: comp-gas
35
The categories of this paper are: mtrl-th
10
The categories of this paper are: q-bio
9
The categories of this paper are: nlin
12
The categories of this paper are: nucl-th
5
The categories of this paper are: gr-qc
28
The categories of this paper are: alg-geom
18
The categories of this paper are: econ
34
The categories of this paper are: chem-ph