English

Information cloning of harmonic oscillator coherent states and its fidelity

Quantum Physics 2007-05-23 v1

Abstract

We show that in the case of unknown {\em harmonic oscillator coherent states} it is possible to achieve what we call {\it perfect information cloning}. By this we mean that it is still possible to make arbitrary number of copies of a state which has {\it exactly} the same information content as the original unknown coherent state. By making use of this {\it perfect information cloning} it would be possible to estimate the original state through measurements and make arbitrary number of copies of the estimator. We define the notion of a {\em Measurement Fidelity}. We show that this information cloning gives rise, in the case of 1N1\to N, to a {\em distribution} of {\em measurement fidelities} whose average value is 12{1\over 2} irrespective of the number of copies originally made. Generalisations of this to the MMNM\to MN case as well as the measurement fidelities for Gaussian cloners are also given.

Keywords

Cite

@article{arxiv.quant-ph/0202020,
  title  = {Information cloning of harmonic oscillator coherent states and its fidelity},
  author = {N. D. Hari Dass and Pradeep Ganesh},
  journal= {arXiv preprint arXiv:quant-ph/0202020},
  year   = {2007}
}

Comments

4 pages(Two column), Revtex