dorsal/arxiv
View SchemaN-body-extended Channel Estimation for Low-Noise Parameters
| Authors | M. Hotta, T. Karasawa, M. Ozawa |
|---|---|
| Categories | |
| ArXiv ID | quant-ph/0609218 |
| URL | https://arxiv.org/abs/quant-ph/0609218 |
| DOI | 10.1088/0305-4470/39/46/015 |
| Journal | J. Phys. A: Math. Gen. 39 No 46 (17 November 2006) 14465-14470 |
Abstract
The notion of low-noise channels was recently proposed and analyzed in detail in order to describe noise-processes driven by environment [M. Hotta, T. Karasawa and M. Ozawa, Phys. Rev. A72, 052334 (2005)]. An estimation theory of low-noise parameters of channels has also been developed. In this report, we address the low-noise parameter estimation problem for the $N$-body extension of low-noise channels. We perturbatively calculate the Fisher information of the output states in order to evaluate the lower-bound of the mean-square error of the parameter estimation. We show that the maximum of the Fisher information over all input states can be attained by a factorized input state in the leading order of the low-noise parameter. Thus, to achieve optimal estimation, it is not necessary for there to be entanglement of the $N$ subsystems, as long as the true low-noise parameter is sufficiently small.
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"abstract": "The notion of low-noise channels was recently proposed and analyzed in detail\nin order to describe noise-processes driven by environment [M. Hotta, T.\nKarasawa and M. Ozawa, Phys. Rev. A72, 052334 (2005)]. An estimation theory of\nlow-noise parameters of channels has also been developed. In this report, we\naddress the low-noise parameter estimation problem for the $N$-body extension\nof low-noise channels. We perturbatively calculate the Fisher information of\nthe output states in order to evaluate the lower-bound of the mean-square error\nof the parameter estimation. We show that the maximum of the Fisher information\nover all input states can be attained by a factorized input state in the\nleading order of the low-noise parameter. Thus, to achieve optimal estimation,\nit is not necessary for there to be entanglement of the $N$ subsystems, as long\nas the true low-noise parameter is sufficiently small.",
"arxiv_id": "quant-ph/0609218",
"authors": [
"M. Hotta",
"T. Karasawa",
"M. Ozawa"
],
"categories": [
"quant-ph"
],
"doi": "10.1088/0305-4470/39/46/015",
"journal_ref": "J. Phys. A: Math. Gen. 39 No 46 (17 November 2006) 14465-14470",
"title": "N-body-extended Channel Estimation for Low-Noise Parameters",
"url": "https://arxiv.org/abs/quant-ph/0609218"
},
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