Future gravitational wave observation in space will demand improvement in the sensitivity of the local sensor for the drag-free control. This paper presents the proposal, design, and demonstration of a new laser interferometric sensor named Quadrature Interferometric Metrology of Translation and Tilt (QUIMETT) for the drag-free local sensor. QUIMETT enables simultaneous measurements of both translational displacement and tilts of a reflective object with a single interferometer package. QUIMETT offers a characteristic feature where the sensitivity to tilt is independent of the interference condition while maintaining the ability to measure the translational displacement for a range greater than the laser wavelength. The tilt-sensing function has been demonstrated in a prototype experiment. The tilt sensitivity remained unchanged in different interference conditions and stayed at 10 nrad/Hz1/2 at 0.1 Hz.
@article{arxiv.2410.23887,
title = {Demonstration of tilt sensing using a homodyne quadrature interferometric translational sensor},
author = {Koji Nagano and Karera Mori and Kiwamu Izumi},
journal= {arXiv preprint arXiv:2410.23887},
year = {2025}
}