New Design of Electrostatic Mirror Actuators for Application in High-Precision Interferometry

TL;DR

This paper introduces a novel electrostatic mirror actuator design that maintains the mirror's aperture, offers a significant reduction in motion coupling, and can be integrated without compromising seismic isolation in high-precision interferometers.

Contribution

The paper presents a new electrostatic actuator geometry that preserves mirror aperture and reduces motion coupling, suitable for high-precision laser interferometry.

Findings

Actuator range of 0.28 micrometers at 1 kV for the AEI-10m interferometer

Reduction factor of about 100 in actuator motion coupling

Ability to mount actuators directly on the optical table without affecting seismic isolation

Abstract

We describe a new geometry for electrostatic actuators to be used in sensitive laser interferometers. The arrangement consists of two plates at the sides of the mirror (test mass), and therefore does not reduce its clear aperture as a conventional electrostatic drive (ESD) would do. Using the sample case of the AEI-10m prototype interferometer, we investigate the actuation range and influences of relative misalignment of the ESD plates in respect to the test mass. We find that in the case of the AEI-10 m prototype interferometer, this new kind of ESD could provide a range of 0.28 micrometer when operated at a voltage of 1 kV. In addition, the geometry presented is shown to provide a reduction factor of about 100 in the magnitude of actuator motion coupling to test mass displacement. We show that therefore in the specific case of the AEI-10m interferometer it is possible to mount the ESD actuators directly on the optical table, without spoiling the seismic isolation performance of the triple stage suspension of the main test masses.