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arXiv · 2308.12813

Quantum state tomography of photon's polarization and path degrees of freedom

J. L. Montenegro Ferreira·B. de Lima Bernardo
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Abstract

Quantum state tomography (QST), the process through which the density matrix of a quantum system is characterized from measurements of specific observables, is a fundamental pillar in the fields of quantum information and computation. In this work, we propose a simple QST method to reconstruct the density matrix of two qubits encoded in the polarization and path degrees of freedom of a single photon, which can be realized with a single linear-optical setup. We demonstrate that the density matrix can be fully described in terms of the Stokes parameters related to the two possibles paths of the photon, together with a quantum version of the two-point Stokes parameters introduced here. Our findings put forward photonic circuits for the investigation of the dynamics of open quantum systems.

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J. L. Montenegro Ferreira, B. de Lima Bernardo. 2023-08-24. Quantum state tomography of photon's polarization and path degrees of freedom. https://arxiv.org/abs/2308.12813

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