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Minimum construction of two-qubit quantum operations

Jun Zhang·Jiri Vala·Shankar Sastry·K. Birgitta Whaley
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Abstract

Optimal construction of quantum operations is a fundamental problem in the realization of quantum computation. We here introduce a newly discovered quantum gate, B, that can implement any arbitrary two-qubit quantum operation with minimal number of both two- and single-qubit gates. We show this by giving an analytic circuit that implements a generic nonlocal two-qubit operation from just two applications of the B gate. We also demonstrate that for the highly scalable Josephson junction charge qubits, the B gate is also more easily and quickly generated than the CNOT gate for physically feasible parameters.

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Jun Zhang, Jiri Vala, Shankar Sastry, K. Birgitta Whaley. 2004-05-13. Minimum construction of two-qubit quantum operations. https://doi.org/10.1103/physrevlett.93.020502

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