Local and nonlocal probabilistic cloning of qubit states via partially entangled twin photons

TL;DR

This paper investigates probabilistic cloning of qubit states using partially entangled photons, demonstrating that errors from partial entanglement can be corrected via quantum state discrimination, enabling perfect clones with certain success probability.

Contribution

It extends the nonlocal probabilistic cloning protocol to partially entangled states and introduces a method to correct errors through quantum state discrimination.

Findings

Errors from partial entanglement can be corrected by quantum state discrimination.

Perfect clones are achievable with a certain success probability.

The setup can be modified to produce local copies.

Abstract

Recently, the nonlocal optimal probabilistic cloning (NLOPC) of two non-orthogonal qubit states has been proposed [Phys. Rev. A 86, 052332 (2012)] by means of an experimental setup based on a pair of twin photons in a maximally entangled state. Here we study the performance of the NLOPC protocol when implemented via a partially entangled state. We show that the errors introduced by the use of partial entanglement can be undone by applying a quantum state discrimination process. Since quantum state discrimination is a probabilistic process the correction succeeds with a certain probability but produces perfect clones. We also studied how to modified the setup to produce local copies.