Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Spin squeezing of the non-Hermitian one-axis twisting model   In the absence of decay, the conditional dynamics for an opensystem is often
describable by a non-Hermitian Hamiltonian. This study investigates spin
squeezing (SS) in non-Hermitian one-axis twisting (OAT) model. Somewhat
surprisingly, SS close to the limit of Hermitian two-axis counter twisting
(TACT) Hamiltonian is achievable for some parameters, which significantly
improves upon the optimal value realizable by Hermitian OAT model. The drawback
is like with all conditional schemes, it takes on average longer time to evolve
into steady state, and the probability of no decay or success decreases as
number of atoms (spins) increases. The result above for steady state SS in
non-Hermitian OAT Hamiltonian is thus limited to small systems. For other
parameter regimes, however, desirable SS arrives dynamically before steady
state is achieved, with greatly shortened evolution time and enhanced
probability of success, while still remain significantly improved over the
limit of Hermitian OAT.

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The categories of this paper are: physics
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The categories of this paper are: acc-phys
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The categories of this paper are: ao-sci
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The categories of this paper are: astro-ph
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The categories of this paper are: q-bio
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The categories of this paper are: comp-gas
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The categories of this paper are: hep-th
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The categories of this paper are: math
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The categories of this paper are: cmp-lg
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The categories of this paper are: hep-lat
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The categories of this paper are: q-fin
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The categories of this paper are: cs
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The categories of this paper are: nucl-ex
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The categories of this paper are: cond-mat
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The categories of this paper are: plasm-ph
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The categories of this paper are: patt-sol