# Cloning a qutrit

@article{Cerf2002CloningAQ, title={Cloning a qutrit}, author={Nicolas J. Cerf and Thomas Durt and Nicolas Gisin}, journal={Journal of Modern Optics}, year={2002}, volume={49}, pages={1355 - 1373} }

Several classes of state-dependent quantum cloners for three-level systems are investigated. These cloners optimally duplicate some of the four maximally-conjugate bases with an equal fidelity, thereby extending the phasecovariant qubit cloner to qutrits. Three distinct classes of qutrit cloners can be distinguished, depending on whether two, three, or four maximally-conjugate bases are cloned as well (the latter case simply corresponds to the universal qutrit cloner). These results apply to…

## 36 Citations

Covariant cloning machines for four-level systems

- Physics
- 2003

The study of quantum cryptography and quantum entanglement has traditionally been based on two-level quantum systems (qubits) and more recently on three-level systems (qutrits). We investigate…

ALTERNATIVE DERIVATION OF THE CRITERION FOR ECONOMICAL REALIZATION OF ONE-TO-TWO QUBIT CLONING

- Economics
- 2006

In a previous paper [Phys. Rev. A69 (2004) 062316], two of us (JD and TD) derived a necessary and sufficient condition for the reducibility of 3 qubit one-to-two cloners to 2 qudit one-to-two…

Security of Quantum Key Distribution with entangled Qutrits.

- Computer Science, Physics
- 2003

This paper considers a generalization of Ekert's entanglement-based quantum cryptographic protocol where qubits are replaced by three-level systems (qutrits), and exhibits the explicit form of this cloner, which is distinct from the previously known cloners.

Cloning a real d-dimensional quantum state on the edge of the no-signaling condition

- Physics
- 2003

We investigate the class of quantum cloning machines that equally duplicate all real states in a Hilbert space of arbitrary dimension. By using the no-signaling condition, namely, that cloning cannot…

Process-optimized phase-covariant quantum cloning

- Computer SciencePhysical Review A
- 2022

The optimal global fidelity for phase-covariant cloning machines via semi-definite programming optimization is computed, thereby completing a remaining gap in the previous results on QCMs.

Extremal quantum cloning machines

- Mathematics
- 2005

We investigate the problem of cloning a set of states that is invariant under the action of an irreducible group representation. We then characterize the cloners that are extremal in the convex set…

Scheme for realizing ancilla-free 1→M economic phase-covariant quantum cloning of qubits and qutrits

- Physics
- 2006

Economical quantum cloning in any dimension

- Physics
- 2005

The possibility of cloning a d-dimensional quantum system without an ancilla is explored, extending on the economical phase-covariant cloning machine for qubits found in Phys. Rev. A 60, 2764 (1999).…

A cloned qutrit and its utility in information processing tasks

- Computer ScienceQuantum Inf. Process.
- 2014

This work analyzes the efficacy of an output as a resource from a universal quantum cloning machine in information processing tasks such as teleportation and dense coding and finds the output states are found to be NPT states for a certain range of machine parameters.

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