Enhanced characteristics of fused silica fibers using laser polishing

Heptonstall, A. et al. (2014) Enhanced characteristics of fused silica fibers using laser polishing. Classical and Quantum Gravity, 31(10), p. 105006. (doi: 10.1088/0264-9381/31/10/105006)

Abstract

The search for gravitational wave signals from astrophysical sources has led to the current work to upgrade the two largest of the long-baseline laser interferometers, the LIGO detectors. The first fused silica mirror suspensions for the Advanced LIGO gravitational wave detectors have been installed at the LIGO Hanford and Livingston sites. These quadruple pendulums use synthetic fused silica fibers produced using a CO₂ laser pulling machine to reduce thermal noise in the final suspension stage. The suspension thermal noise in Advanced LIGO is predicted to be limited by internal damping in the surface layer of the fibers, damping in the weld regions, and the strength of the fibers. We present here a new method for increasing the fracture strength of fused silica fibers by laser polishing of the stock material from which they are produced. We also show measurements of mechanical loss in laser polished fibers, showing a reduction of 30% in internal damping in the surface layer.

• Item Type: Articles
• Status: Published
• Refereed: Yes
• Glasgow Author(s) Enlighten ID: Grant, Mr Alastair and Cagnoli, Dr Gianpietro and Heptonstall, Dr Alastair and Rowan, Professor Sheila and Kumar, Mr Rahul and Bell, Dr Angus and Martin, Dr Iain and Hammond, Professor Giles and Hough, Professor James and Cumming, Dr Alan and Tokmakov, Dr Kirill and Strain, Professor Kenneth and Jones, Mr Russell and Robertson, Mr Neil and Barton, Dr Mark
• Authors: Heptonstall, A., Barton, M. A., Bell, A. S., Bohn, A., Cagnoli, G., Cumming, A., Grant, A., Gustafson, E., Hammond, G. D., Hough, J., Jones, R., Kumar, R., Lee, K., Martin, I. W., Robertson, N. A., Rowan, S., Strain, K. A., and Tokmakov, K. V.
• College/School: College of Science and Engineering > School of Physics and Astronomy
• Research Centre: College of Science and Engineering > School of Physics and Astronomy > Institute for Gravitational Research
• Journal Name: Classical and Quantum Gravity
• Publisher: IOP Publishing
• ISSN: 0264-9381
• ISSN (Online): 1361-6382
• Copyright Holders: Copyright © 2014 The Authors
• First Published: First published in Classical and Quantum Gravity 31(10):105006
• Publisher Policy: Reproduced under a Creative Commons License

Project Code	Award No	Project Name	Principal Investigator	Funder's Name	Funder Ref	Lead Dept
45931	3	Investigations in Gravitational Radiation.	Sheila Rowan	Science & Technologies Facilities Council (STFC)	ST/J000361/1	P&A - PHYSICS & ASTRONOMY