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arXiv · 1609.00370

Quantum phase estimation using squeezed quasi-Bell states

Douglas Delgado de Souza·A. Vidiella-Barranco
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Abstract

In this paper we present a study of the quantum phase estimation problem employing continuous-variable, entangled squeezed coherent (quasi-Bell) states as probe states. We show that their inherent squeezing and entanglement properties might bring advantages, increasing the precision of phase estimation compared to protocols which employ other continuous variable states e.g., two-mode, entangled coherent states or single-mode, squeezed states. We also analyze the phase estimation process considering: i) a linear (unitary) perturbation, and ii) dissipation, and conclude that the use of entangled squeezed coherent states as probe states may still be advantageous even under non-ideal conditions.

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Douglas Delgado de Souza, A. Vidiella-Barranco. 2016-09-01. Quantum phase estimation using squeezed quasi-Bell states. https://doi.org/10.1016/j.ijleo.2021.167532

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