Quantum-Assisted Optical Interferometers: Instrument Requirements

TL;DR

This paper proposes a quantum-assisted optical interferometry method that enables high-precision relative astrometry between sources using decoupled stations and classical communication, requiring specific instrument capabilities.

Contribution

It introduces a novel interferometry approach with photons from different sources at separate stations, reducing phase stability requirements and enabling new astrophysical measurements.

Findings

Potential angular resolution of 10 microarcseconds in hours

Instrument requirements include high temporal and spectral resolution

Discussion of technological implementations and proof-of-principle experiments

Abstract

It has been recently suggested that 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 extra-long baselines and benefiting numerous topics in astrophysics and cosmology. We developed a new variation of this idea, proposing that photons from two different sources could be interfered at two decoupled stations, requiring only a slow classical connection between them. We show that this approach could allow high-precision measurements of the relative astrometry of the two sources, with a simple estimate giving angular resolution of $10 \ \mu$as in a few hours' observation of two bright stars. We also give requirements on the instrument for these observations, in particular on its temporal and spectral resolution. Finally, we discuss possible technologies for the instrument implementation and first proof-of-principle experiments.