# Quantum cloning of mixed states in symmetric subspaces

@article{Fan2003QuantumCO, title={Quantum cloning of mixed states in symmetric subspaces}, author={Heng Fan}, journal={Physical Review A}, year={2003}, volume={68}, pages={054301} }

Quantum-cloning machine for arbitrary mixed states in symmetric subspaces 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.

## 16 Citations

Quantum Cloning Machines

- Physics
- 2006

This Chapter is a review of various quantum cloning machines. The author focuses on several well-studied quantum cloning machines: universal quantum cloning machines, phase-covariant quantum cloning…

Assisted Cloning and Orthogonal Complementing of an Arbitrary Unknown Two-Qubit Entangled State

- Physics
- 2006

Based on A.K. Pati's original idea [Phys. Rev. A 61 (2000) 022308] on single-qubit-state-assisted clone, very recently Zhan has proposed two assisted quantum cloning protocols of a special class of…

SCHEME FOR QUANTUM CLONING OF AN UNKNOWN N-PARTICLE ENTANGLED STATE WITH ASSISTANCE

- Physics
- 2008

In this paper, we present a scheme which can realize quantum cloning of an unknown N-particle entangled state and its orthogonal complement state with assistance offered by a state preparer. The…

Scheme for Implementing Assisted Cloning of an Unknown d-Dimension Equatorial Quantum State by Remote State Preparation

- Mathematics
- 2009

A protocol is proposed that can produce perfect copy of an unknown d-dimensional equatorial quantum state with assistance from a state preparer and the maximally and non-maximally entangled bipartite d- dimensional of states are used as the quantum channels.

Assisted Cloning and Orthogonal Complementing of an Arbitrary Unknown Two-qubit Entangled State via Positive Operator-valued Measure

- Physics
- 2009

By using positive operator-valued measure (POVM) instead of the more commonly used collective unitary operation in the quantum teleportation process, Zhan’s scheme (Zhan in Phys. Lett. A 336:317,…

SCHEME FOR IMPLEMENTING ASSISTED CLONING OF AN UNKNOWN BIPARTITE THREE-DIMENSION EQUATORIAL ENTANGLED STATE

- Computer Science
- 2007

In this paper, we proposed a protocol which can produce a perfect copy of an unknown bipartite three-dimension equatorial entangled state with assistance from a state preparer. In this protocol, the…

SCHEME FOR IMPLEMENTING ASSISTED CLONING OF AN UNKNOWN BIPARTITE D-DIMENSION EQUATORIAL ENTANGLED STATE

- Mathematics
- 2008

In this paper, we proposed a protocol which can produce a perfect copy of an unknown bipartite d-dimension equatorial entangled state with assistance from a state preparer. In this protocol, the…

Scheme for Cloning an Unknown Entangled State with Assistance via Non-maximally Entangled Cluster States

- Physics
- 2009

We propose a scheme for cloning unknown two-particle entangled state and its orthogonal complement state with assistance from a state preparer. Two stages were included in this scheme. The first…

Partitioned trace distances

- Computer ScienceQuantum Inf. Process.
- 2010

New quantum distance is introduced as a half-sum of several singular values of difference between two density operators. This is, up to factor, the metric induced by so-called Ky Fan norm. The…

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