dorsal/arxiv
View SchemaMeasuring polynomial functions of states
| Authors | Todd A. Brun |
|---|---|
| Categories | |
| ArXiv ID | quant-ph/0401067 |
| URL | https://arxiv.org/abs/quant-ph/0401067 |
| Journal | Quantum Information and Computation 4, 401 (2004). |
Abstract
In this paper I show that any $m$th-degree polynomial function of the elements of the density matrix $\rho$ can be determined by finding the expectation value of an observable on $m$ copies of $\rho$, without performing state tomography. Since a circuit exists which can approximate the measurement of any observable, in principle one can find a circuit which will estimate any such polynomial function by averaging over many runs. I construct some simple examples and compare these results to existing procedures.
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"abstract": "In this paper I show that any $m$th-degree polynomial function of the\nelements of the density matrix $\\rho$ can be determined by finding the\nexpectation value of an observable on $m$ copies of $\\rho$, without performing\nstate tomography. Since a circuit exists which can approximate the measurement\nof any observable, in principle one can find a circuit which will estimate any\nsuch polynomial function by averaging over many runs. I construct some simple\nexamples and compare these results to existing procedures.",
"arxiv_id": "quant-ph/0401067",
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"journal_ref": "Quantum Information and Computation 4, 401 (2004).",
"title": "Measuring polynomial functions of states",
"url": "https://arxiv.org/abs/quant-ph/0401067"
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