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arXiv:2407.11570 · EPJ Quantum Technology

Undergraduate setup for measuring the Bell inequalities and performing quantum state tomography

Raul Lahoz Sanz, Lidia Lozano‐Martín, A. B. CORTES, Martí Duocastella, Jose M. Gomez, Bruno Juliá-Díaz

Published Dec 1, 2024• 3 citations
arXivHTMLPDF

Abstract

The growth of quantum technologies is attracting the interest of many students eager to learn concepts such as quantum entanglement or quantum superposition. However, the non-intuitive nature of these concepts poses a challenge to understanding them. Here, we present an entangled photon system which can perform a Bell test, i.e. the CHSH inequality, and can obtain the complete tomography of the two-photon state. The proposed setup is versatile, cost-effective and allows for multiple classroom operating modes. We present two variants, both facilitating the measurement of Bell inequalities and quantum state tomography. Experimental results showcase successful manipulation of the quantum state of the photons, achieving high-fidelity entangled states and significant violations of Bell's inequalities. Our setup's simplicity and affordability enhances accessibility for less specialized laboratories, allowing students to familiarize themselves with quantum physics concepts.

DOI
10.1140/epjqt/s40507-024-00298-y

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