Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Certified quantum non-demolition measurement of material systems   An extensive debate on quantum non-demolition (QND) measurement, reviewed in
Grangier et al. [Nature, {\bf 396}, 537 (1998)], finds that true QND
measurements must have both non-classical state-preparation capability and
non-classical information-damage tradeoff. Existing figures of merit for these
non-classicality criteria require direct measurement of the signal variable and
are thus difficult to apply to optically-probed material systems. Here we
describe a method to demonstrate both criteria without need for to direct
signal measurements. Using a covariance matrix formalism and a general noise
model, we compute meter observables for QND measurement triples, which suffice
to compute all QND figures of merit. The result will allow certified QND
measurement of atomic spin ensembles using existing techniques.

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The categories of this paper are: math-ph
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The categories of this paper are: plasm-ph
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The categories of this paper are: patt-sol
9
The categories of this paper are: nlin
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The categories of this paper are: cond-mat
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The categories of this paper are: chem-ph
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The categories of this paper are: hep-ex
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The categories of this paper are: hep-lat
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The categories of this paper are: ao-sci
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The categories of this paper are: funct-an
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The categories of this paper are: cs
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The categories of this paper are: econ
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The categories of this paper are: acc-phys
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The categories of this paper are: dg-ga
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The categories of this paper are: adap-org
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The categories of this paper are: q-alg