Quantum Cloning of Mixed States in Symmetric Subspace

Abstract

Quantum cloning machine for arbitrary mixed states in symmetric subspace is proposed. This quantum cloning machine can be used to copy part of the output state of another quantum cloning machine and is useful in quantum computation and quantum information. The shrinking factor of this quantum cloning achieves the well-known upper bound. When the input is identical pure states, two different fidelities of this cloning machine are optimal.

Revtex, 4 pages

References in corpus (11)

• Security of quantum key distribution using d-level systems
• Quantum Copying: Beyond the No-Cloning Theorem
• Optimal Quantum Cloning Machines
• Optimal Cloning of Pure States
• Optimal eavesdropping in cryptography with three-dimensional quantum states
• Optimal universal quantum cloning and state estimation
• Quantum cloning and the capacity of the Pauli channel
• Optimal Cloning of Pure States, Judging Single Clones
• Asymmetric quantum cloning machines in any dimension
• Quantum Cloning in $d$ dimensions
• Cloning of symmetric d-level photonic states in physical systems

Cited by in corpus (5)

• Quantum Cloning Machines and the Applications
• Partitioned trace distances
• Mixed Qubit Cannot Be Universally Broadcast
• Optimal Broadcasting of Mixed States
• Variational quantum cloning machine on an integrated photonic interferometer