Efficient amplification of photonic qubits by optimal quantum cloning
Efficient amplification of photonic qubits by optimal quantum cloning
We demonstrate that a phase-independent quantum amplifier of a polarization qubit is a complementary amplifier of the heralded qubit amplifier [N. Gisin, S. Pironio, and N. Sangouard, Phys. Rev. Lett. 105, 070501 (2010)]. It employs the multifunctional cloner in the $1\ensuremath{\rightarrow}2$ copying regime, capable of providing approximate copies of qubits …