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arXiv · 2205.13288

Noise resilience in path-polarization hyperentangled probe states

Akshay Kannan Sairam·C. M. Chandrashekar
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Abstract

Most quantum systems that are used for generating entanglement and for practical applications are not isolated from the environment, and are hence susceptible to noise. Entanglement in more than one degree of freedom between two systems, known as hyperentanglement, is known to have certain advantages, including robustness against noise over conventional entangled states. Quantum illumination, imaging and communication schemes that involve sending one photon from a pair of entangled photons and retaining the other photon usually involve exposing only the signal photon to environmental noise. The disruptive nature of noise degrades entanglement and other correlations which are crucial for many of these applications. In this paper, we study the advantages of using photon pairs in certain path-polarization hyperentangled states in a noisy interaction where photons in only one of the paths are affected by noise. We model such noise and study the effect of noise on the correlations present in the hyperentangled photons. Three different methods, entanglement negativity, entanglement witnesses and Bell nonlocality are used to show the resilience of path-polarization hyperentangled probe state against noise.

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Akshay Kannan Sairam, C. M. Chandrashekar. 2022-05-26. Noise resilience in path-polarization hyperentangled probe states. https://doi.org/10.1088/1361-6455/ac9871

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