Entanglement witness measurement of time-bin two-qubit states using fiber-based Franson interferometers

Entanglement, that is, quantum correlations that do not have a classical counterpart, is a precondition to establishing communication protocols beyond the existing classical protocols, such as quantum key distribution, that achieves a higher level of security without computational assumptions. In th...

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Bibliographic Details
Main Authors: Kyumin Hwang, Jiheon Seong, Kyungdeuk Park, Jinwook Kim, Tanumoy Pramanik, Joonwoo Bae, Heedeuk Shin
Format: Article
Language:English
Published: Frontiers Media S.A. 2023-08-01
Series:Frontiers in Physics
Subjects:
Online Access:https://www.frontiersin.org/articles/10.3389/fphy.2023.1254044/full
Description
Summary:Entanglement, that is, quantum correlations that do not have a classical counterpart, is a precondition to establishing communication protocols beyond the existing classical protocols, such as quantum key distribution, that achieves a higher level of security without computational assumptions. In this work, we present a proof of demonstration of detecting various entangled states, prepared by time-bin encoding with photons that are natural resources for long-distance quantum communication. We generate a maximally entangled state in time-bin qubits and verify the state in two ways. We first consider measurements that realize entanglement witnesses for the verification of entanglement. We then perform a quantum state tomography for the full characterization. Experimental resources are also discussed.
ISSN:2296-424X