A compact actively damped vibration isolation platform for optical experiments in ultra-high vacuum

TL;DR

This paper introduces a compact, actively damped vibration isolation platform compatible with ultra-high vacuum, designed for optical experiments, providing significant vibration reduction across multiple axes with adaptable footprint and demonstrated effectiveness in LIGO applications.

Contribution

The paper presents a novel, cost-effective, and adaptable six-axis vibration isolation system with active damping suitable for ultra-high vacuum environments, tailored for optical experiments.

Findings

Achieves 25 dB isolation at 10 Hz and 65 dB at 100 Hz

Supports six degrees of freedom with passive and active components

Currently deployed in three LIGO units

Abstract

We present a tabletop six-axis vibration isolation system, compatible with Ultra-High Vacuum (UHV), which is actively damped and provides 25 dB of isolation at 10 Hz and 65 dB at 100 Hz. While this isolation platform has been primarily designed to support optics in the Laser Interferometer Gravitational-Wave Observatory (LIGO) detectors, it is suitable for a variety of applications. The system has been engineered to facilitate the construction and assembly process, while minimizing cost. The platform provides passive isolation for six degrees of freedom using a combination of vertical springs and horizontal pendula. It is instrumented with voice-coil actuators and optical shadow sensors to damp the resonances. All materials are compatible with stringent vacuum requirements. Thanks to its architecture, the system's footprint can be adapted to meet spatial requirements, while maximizing the dimensions of the optical table. Three units are currently operating for LIGO. We present the design of the system, controls principle, and experimental results.