Phase-covariant cloning of coherent states

Abstract

We consider the problem of phase-covariant cloning for coherent states. We show that an experimental scheme based on ideal phase measurement and feedforward outperforms the semiclassical procedure of ideal phase measurement and preparation in terms of fidelity. A realistic scheme where the ideal phase measurement is replaced with double-homodyne detection is shown to be unable to overcome the semiclassical cloning strategy. On the other hand, such a realistic scheme is better than semiclassical cloning based on double-homodyne phase measurement and preparation.

6 pages, 2 figures; updated references and minor corrections; in press on Physical Review A

References in corpus (27)

• Quantum Cryptography
• Quantum Copying: Beyond the No-Cloning Theorem
• Optimal Quantum Cloning Machines
• Optimal Universal and State-Dependent Quantum Cloning
• Optimal Cloning of Pure States
• Phase covariant quantum cloning
• Universal cloning of continuous quantum variables
• Quantum Tomography
• Optimal Cloning of Pure States, Judging Single Clones
• Optimal cloning of coherent states with a linear amplifier and beam splitters
• Quantum cloning machines for equatorial qubits
• Unconditional quantum cloning of coherent states with linear optics
• Phase-covariant quantum cloning of qudits
• Optimal phase covariant cloning for qubits and qutrits
• Optimal Non-Universally Covariant Cloning
• Economical Phase-Covariant Cloning of Qudits
• On the general problem of quantum phase estimation
• Superbroadcasting of mixed states
• Realization of the 1->3 optimal phase-covariant quantum cloning machine
• Quantum information becomes classical when distributed to many users
• On the Phase Covariant Quantum Cloning
• Phase-Conjugated Inputs Quantum Cloning Machines
• Physical realizations of quantum operations
• Universal and phase covariant superbroadcasting for mixed qubit states
• Superbroadcasting of continuous variables mixed states
• Superbroadcasting of conjugate quantum variables
• Unitary realizations of the ideal phase measurement

Cited by in corpus (7)

• Surpassing the no-cloning limit with a heralded hybrid linear amplifier for coherent states
• Probabilistic Cloning of Coherent States without a Phase Reference
• Optimal mirror phase-covariant cloning
• Certifying quantumness: Benchmarks for the optimal processing of generalized coherent and squeezed states
• Experimental continuous variable cloning of partial quantum information
• Optimal cloning of qubits given by arbitrary axisymmetric distribution on Bloch sphere
• Truly noiseless probabilistic amplification