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arXiv · 1201.2736

A measurement scheme for purity based on two two-body gates

Hiromichi Nakazato·Toru Tanaka·Kazuya Yuasa·Giuseppe Florio·Saverio Pascazio
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Abstract

A scheme for measuring the purity of a quantum system with a finite number of levels is presented. The method makes use of two square root of SWAP gates and only hinges on measurements performed on a reference system, prepared in a certain pure state and coupled with the target system. Neither tomographic methods, with the complete reconstruction of the state, nor interferometric setups is needed.

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Hiromichi Nakazato, Toru Tanaka, Kazuya Yuasa, Giuseppe Florio, Saverio Pascazio. 2012-02-28. A measurement scheme for purity based on two two-body gates. https://doi.org/10.1103/physreva.85.042316

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