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Realizing quantum advantage without entanglement in single-photon states

Quantum Physics 2017-06-07 v2

Abstract

We discuss the realization of quantum advantage in a system without quantum entanglement but with non-zero quantum discord. We propose an optical realization of symmetric two-qubit XX-states with controllable anti-diagonal elements. This approach does not requires initially entangled states, and it can generate states that have quantum discord, with or without entanglement. We discuss how quantum advantage can be attained in the context of a two-qubit game. We show that when entanglement is not present, the maximum quantum advantage is 1/3 bit. A comparable quantum advantage, 0.311 bit, can be realized with a simplified transaction protocol involving one vs. the three unitary operations needed for the maximum advantage.

Keywords

Cite

@article{arxiv.1604.07351,
  title  = {Realizing quantum advantage without entanglement in single-photon states},
  author = {A. Maldonado-Trapp and Pablo Solano and Anzi Hu and Charles W. Clark},
  journal= {arXiv preprint arXiv:1604.07351},
  year   = {2017}
}
R2 v1 2026-06-22T13:40:22.331Z