15 February 2019
A key component in making the gravitational wave detectors sensitive enough to be able to pick up the ripples in space time are the fused silica suspensions. The mirrors that are used to detect the shifts in gravity are suspended from thin fibres made of fused silica, a type of ultra-pure glass, so that the mirror is held almost perfectly still – so still it can pick up the miniscule changes in gravity.
Each stand is heated up using a carbon dioxide laser beam to make it soft enough to stretch. It is then pulled out into a thin fibre of the desired length. The great thing about silica as a material, is that is can keep being stretched out and still remains very strong. The long strands of silica are so strong that they are able to each hold the weight of a small child, around 40kg, demonstrating the real strength of this material.
Last updated: 25 February 2019