Precision requirements and innovative manufacturing for ultrahigh precision laser interferometry of gravitational-wave astronomy

TL;DR

This paper discusses the precision manufacturing and measurement techniques essential for the development of ultrahigh precision laser interferometry in gravitational-wave astronomy, highlighting recent technological advancements and industry challenges.

Contribution

It provides a comprehensive overview of the manufacturing requirements and diagnostic methods for large optical components used in gravitational-wave detectors.

Findings

Development of large phase-shifting interferometers for optical testing

High-quality mirrors with specific coatings are crucial for detection sensitivity

Advances in vibration isolation and vacuum systems support GW detection

Abstract

With the LIGO announcement of the first direct detection of gravitational waves (GWs), the GW Astronomy was formally ushered into our age. After one-hundred years of theoretical investigation and fifty years of experimental endeavor, this is a historical landmark not just for physics and astronomy, but also for industry and manufacturing. The challenge and opportunity for industry is precision and innovative manufacturing in large size - production of large and homogeneous optical components, optical diagnosis of large components, high reflectance dielectric coating on large mirrors, manufacturing of components for ultrahigh vacuum of large volume, manufacturing of high attenuating vibration isolation system, production of high-power high-stability single-frequency lasers, production of high-resolution positioning systems etc. In this talk, we address the requirements and methods to satisfy these requirements. Optical diagnosis of large optical components requires large phase-shifting interferometer; the 1.06 {\mu}m Phase Shifting Interferometer for testing LIGO optics is an example. High quality mirrors are crucial for laser interferometric GW detection, so as for ring laser gyroscope, high precision laser stabilization via optical cavities, quantum optomechanics, cavity quantum electrodynamics and vacuum birefringence measurement. There are stringent requirements on the substrate materials and coating methods. For cryogenic GW interferometer, appropriate coating on sapphire or silicon are required for good thermal and homogeneity properties. Large ultrahigh vacuum components and high attenuating vibration system together with an efficient metrology system are required and will be addressed. For space interferometry, drag-free technology is well-developed; weak-light phase locking is demonstrated in the laboratories while weak-light manipulation technology still needs developments.