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arXiv · 2506.09770

High-Sensitivity Fiber Interferometer for Gravitational Phase Shift Measurement on Entangled States

Eleonora Polini·Piotr Chruściel·Georgi Dvali·Christopher Hilweg·Begüm Kabagöz·Dorotea Macri·Thomas Mieling·Thomas Morling·Eric Oelker·Elisabeth Steininger·Xinghui Yin·Haocun Yu·Sebastian Zell·Tongxuan Zhang·Nergis Mavalvala·Philip Walther
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Abstract

In this contribution, we describe the status of our experiment aimed at measuring the gravitationally induced phase shift on path-entangled photons. We use a kilometer-scale fiber interferometer whose arms are vertically displaced in the Earth gravitational potential, allowing photons propagating at different heights to accumulate different phases. To date, this is the first experiment to measure this effect on massless particles, thereby experimentally combining general relativity and quantum mechanics.

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Eleonora Polini, Piotr Chruściel, Georgi Dvali, Christopher Hilweg, Begüm Kabagöz, Dorotea Macri, Thomas Mieling, Thomas Morling, Eric Oelker, Elisabeth Steininger, Xinghui Yin, Haocun Yu, Sebastian Zell, Tongxuan Zhang, Nergis Mavalvala, Philip Walther. 2025-06-11. High-Sensitivity Fiber Interferometer for Gravitational Phase Shift Measurement on Entangled States. https://arxiv.org/abs/2506.09770

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