Optimal and scalable telecloning in a limited-control scenario

Quantum telecloning [1] is a Quantum Information Processing task, which allows to achieve optimal spreading among N receivers of the quantum information initially possessed by one sender. So far, to the best of our knowledge, no scheme for the actual implementation of such a process in a scalable way has been proposed. Here, we first show the existence of a class of many-qubit singlets allowing for optimal and scalable telecloning. Next, we illustrate a protocol to prepare such states in a setting where scattering centers possessing a spin degree of freedom interact by means of mobile particles. The scheme is understood simply by resorting to an appropriate coupling scheme for the addition of angular momenta and Hamiltonian symmetries. Major practical advantages of our scheme lie on the management of stationary and well separated spins along with the mild requirement to perform simple Geiger measurements over the mobile particles to establish the necessary multipartite entanglement [3, 4]. We also show strategies that allow generating in the same setting other important many-qubit states such as Aharonov, W and GHZ states.

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[2] F. Ciccarello, M. Paternostro, S. Bose, D. Browne, G. M. Palma and M. Zarcone, arXiv:1003.2171 (2010).
[3] F. Ciccarello, M. Paternostro, G. M. Palma and M. Zarcone, New J. Phys. 11, 113053 (2009).
[4] F. Ciccarello, S. Bose and M. Zarcone, Phys. Rev. A 81, 042318 (2010).