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arXiv · 2507.04134

Revealing Bosonic Exchange Symmetry in Two-Photon Temporal Wavefunction

Yefeng Mei·Yue Jiang·Shengwang Du
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Abstract

The wavefunction of two identical bosons remains invariant under particle exchange - a fundamental quantum symmetry that underlies Bose-Einstein statistics. We report the direct experimental observation of bosonic exchange symmetry in the temporal wavefunction of photon pairs generated via spontaneous four-wave mixing in a three-level cold atomic ensemble. The measured two-photon temporal correlations show excellent agreement with theoretical predictions based on symmetrized bosonic wavefunctions. In addition, we perform time-resolved two-photon interference to reconstruct the complex temporal wavefunction. Both the amplitude and phase profiles exhibit clear symmetry under photon exchange, providing a direct confirmation of bosonic exchange symmetry in the time domain.

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Yefeng Mei, Yue Jiang, Shengwang Du. 2025-07-05. Revealing Bosonic Exchange Symmetry in Two-Photon Temporal Wavefunction. https://doi.org/10.1103/sq4j-53jr

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