Detecting Earth’s rotation using entangled photons

Giampaolo Pitruzzello

Raffaele Silvestri, Haocun Yu, Robert W. Peterson +2 more

We present the first experimental measurement of the Earth’s rotation induced phase shift on a two-photon maximally entangled state by means of a large-scale fiber Sagnac interferometer of milliradian phase resolution.

Zhi Chen, ANDREI NOMEROTSKI, Anže Slosar +2 more

Optical interferometers may not require a phase-stable optical link between the stations if instead sources of quantum-mechanically entangled pairs could be provided to them, enabling long baselines. We developed a new variation of this idea, proposing that photons from two different astronomical sources could be interfered at two decoupled stations. Interference products can then be calculated in post-processing or requiring only a slow, classical connection between stations. In this work, we investigated practical feasibility of this approach. We developed a Bayesian analysis method for the earth rotation fringe scanning technique and showed that in the limit of high signal-to-noise ratio it reproduced the results from a simple Fisher matrix analysis. We identify candidate stair pairs in the northern hemisphere, where this technique could be applied. With two telescopes with an effective collecting area of $\ensuremath{\sim}2\text{ }\text{ }{\mathrm{m}}^{2}$, we could detect fringing and measure the astrometric separation of the sources at $\ensuremath{\sim}100\text{ }\text{ }\mathrm{\ensuremath{\mu}}\mathrm{as}$ precision in a few hours of observations, in agreement with previous estimates.

Amaal M. Ali, Natasha Bastien, Wendy-Ann Gibbons +2 more

Min She, Jiang-Shan Tang, Keyu Xia

A high-sensitivity gyroscope is vital for both investigation of the fundamental physics and monitoring of the subtle variation of Earth’s behaviors. However, it is a challenge to realize a portable gyroscope with sensitivity approaching a small fraction of the Earth’s rotation rate. Here, we theoretically propose a method for implementing a table-top gyroscope with remarkably high sensitivity based on photon drag in a rotating dielectric object. By inserting an Er3+-doped glass rod in a Fabry–Pérot optical cavity with only 20 cm length, we theoretically show that the giant group refractive index and the narrowing cavity linewidth due to slow light can essentially increase the nonreciprocal phase shift due to the photon drag to achieve a rotation sensitivity of 26 frad/s/Hz. This work paves the way to accurately detect tiny variations of the Earth’s rotation rate and orientation and even can test the geodetic and frame-dragging effects predicted by the general relativity with small-volume equipment.

Oza, Altepeter, Medic +2 more