Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Quantum analogue of the spin-flop transition for a spin pair   Quantum (step-like) magnetization curves are studies for a spin pair with
antiferromagnetic coupling in the presence of a magnetic field parallel to the
easy axis of the magnetic anisotropy. The consideration is done both
analytically and numerically for a wide range of the anisotropy constants and
spins up to $S \gtrsim 100$. Depending on the origin of the anisotropy
(exchange or single-ion), the magnetization curve can demonstrate the jumps
more than unity and the concentration of the unit jumps in a narrow range of
the field. We also point the region of the problem parameters, where the
behavior is quasiclassical for $S = 5$, and where system is substantially
quantum in the limit $S \to \infty$.

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The categories of this paper are: q-alg
22
The categories of this paper are: chao-dyn
33
The categories of this paper are: plasm-ph
24
The categories of this paper are: dg-ga
15
The categories of this paper are: nucl-ex
31
The categories of this paper are: ao-sci
11
The categories of this paper are: hep-lat
32
The categories of this paper are: atom-ph
13
The categories of this paper are: quant-ph
10
The categories of this paper are: q-bio
8
The categories of this paper are: hep-ex
6
The categories of this paper are: astro-ph
18
The categories of this paper are: econ
23
The categories of this paper are: solv-int
25
The categories of this paper are: patt-sol
16
The categories of this paper are: stat