Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Impact of Non-Unitary Spin Squeezing on Atomic Clock Performance   Spin squeezing is a form of entanglement that can improve the stability of
quantum sensors operating with multiple particles, by inducing inter-particle
correlations that redistribute the quantum projection noise. Previous analyses
of potential metrological gain when using spin squeezing were performed on
theoretically ideal states, without incorporating experimental imperfections or
inherent limitations which result in non-unitary quantum state evolution. Here,
we show that potential gains in clock stability are substantially reduced when
the spin squeezing is non-unitary, and derive analytic formulas for the clock
performance as a function of squeezing, excess spin noise, and interferometer
contrast. Our results highlight the importance of creating and employing nearly
pure entangled states for improving atomic clocks.

2
The categories of this paper are: math
15
The categories of this paper are: nucl-ex
27
The categories of this paper are: comp-gas
17
The categories of this paper are: q-fin
9
The categories of this paper are: nlin
30
The categories of this paper are: q-alg
6
The categories of this paper are: astro-ph
32
The categories of this paper are: atom-ph
10
The categories of this paper are: q-bio
34
The categories of this paper are: chem-ph
1
The categories of this paper are: cs
23
The categories of this paper are: solv-int
19
The categories of this paper are: eess
12
The categories of this paper are: nucl-th
0
The categories of this paper are: hep-ph
31
The categories of this paper are: ao-sci