arXiv:quant-ph/0306143AbstractReferencesReviewsResources
A quantum gate array can be programmed to evaluate the expectation value of any operator
Juan Pablo Paz, Augusto Roncaglia
Published 2003-06-20Version 1
A programmable gate array is a circuit whose action is controlled by input data. In this letter we describe a special--purpose quantum circuit that can be programmed to evaluate the expectation value of any operator $O$ acting on a space of states of $N$ dimensions. The circuit has a program register whose state $|\Psi(O)>_P$ encodes the operator $O$ whose expectation value is to be evaluated. The method requires knowledge of the expansion of $O$ in a basis of the space of operators. We discuss some applications of this circuit and its relation to known instances of quantum state tomography.
Comments: 4 pages, 3 figures included
Categories: quant-ph
Keywords: expectation value, quantum gate array, quantum state tomography, special-purpose quantum circuit, input data
Tags: journal article
Related articles: Most relevant | Search more
arXiv:1911.10226 [quant-ph] (Published 2019-11-22)
Semiclassical evaluation of expectation values
arXiv:quant-ph/0210106 (Published 2002-10-14)
Universal Formula for the Expectation Value of the Radial Operator under the Aharonov-Bohm Flux and the Coulomb Field
arXiv:2303.16329 [quant-ph] (Published 2023-03-28)
Quantum state engineering by steering in the presence of errors