Optimal mirror phase-covariant cloning
نویسندگان
چکیده
We propose a quantum cloning machine, which clones a qubit into two clones assuming known modulus of expectation value of Pauli z matrix. The process is referred to as the mirror phase-covariant cloning for which the input state is a priori less known than that for the standard phase-covariant cloning. Analytical expressions describing the cloning transformation and fidelity of the clones are found. Extremal equations for the optimal cloning are derived and analytically solved by generalizing a method of Fiurášek Phys. Rev. A 64, 06231
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