Physics – Quantum Physics
Scientific paper
2003-04-23
Physics
Quantum Physics
28 pages, 4 figures, revtex format
Scientific paper
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 several classes of state-dependent quantum cloners for four-level systems (quartits). These results apply to symmetric as well as asymmetric cloners, so that the balance between the fidelity of the two clones can also be analyzed. We extend Cerf's formalism for cloning states in order to derive cloning machines that remain invariant under certain unitary transformations. Our results show that a different cloner has to be used for two mutually unbiased bases which are related by a double Hadamard transformation, than for two mutually unbiased bases that are related by a Fourier transformation. This different cloner is obtained thanks to a redefinition of Bell states that respects the intrinsic symmetries of the Hadamard transformation.
Durt Thomas
Nagler Bob
No associations
LandOfFree
About Covariant Quartit Cloning Machines does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.
If you have personal experience with About Covariant Quartit Cloning Machines, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and About Covariant Quartit Cloning Machines will most certainly appreciate the feedback.
Profile ID: LFWR-SCP-O-108531