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Conditions for optimal construction of two-qubit non-local gates

Yong-Sheng Zhang·Ming-Yong Ye·Guang-Can Guo
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Abstract

Optimal implementation of quantum gates is crucial for designing a quantum computer. The necessary condition for optimal construction of a two-qubit unitary operation is obtained. It can be proved that the B gate is the unique gate that can construct a two-qubit universal circuit with only two applications, i.e. this condition is also sufficient in the case of two applications of the elementary two-qubit gate. It is also shown that one half of perfect entanglers can not simulate an arbitrary two-qubit gate with only 3 applications.

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Yong-Sheng Zhang, Ming-Yong Ye, Guang-Can Guo. 2004-11-09. Conditions for optimal construction of two-qubit non-local gates. https://doi.org/10.1103/physreva.71.062331

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