Scientists from The University of Western Australia’s Centre of Excellence for Gravitational Wave Discovery (OzGrav) are part of a global team of researchers that has made a surprising discovery, working out how to break quantum limits. The research was published in the prestigious Nature journal.
A quantum limit comes about from the interaction between light and a test mass, and breaking this limit, just like breaking the sound barrier, once seemed impossible.
The scientists surpassed the limit in their quest to build better gravitational wave detectors using squeezed light technology on 40kg test masses in LIGO detectors.
The technology was pioneered by the Australian National University and refined at Massachusetts Institute of Technology, which led to the development of the squeezed light apparatus at the LIGO and the groundbreaking result.
Gravitational wave detectors are the most precise measurement devices ever built, and the result shows they are now poised to see and exploit the effects of quantum physics, which governs the smallest objects in the universe, on human-sized objects like their 40kg test masses.
UWA physicist Dr Carl Blair, who was part of the team to make the discovery said discovering how to break quantum limits was significant for physics and science.
“It’s amazing to think that sitting in the control room at LIGO, by manipulating some controls on a computer you can manipulate the quantum noise of a 40 kg mirror,” he said.
“We were able to break the limit doing something very mysterious – squeezing the quantum vacuum,” he said.
“Now that it has been proven possible, this new technology can be used to build more sensitive machines to explore the Universe.
“In breaking this limit, we are now entering a world where quantum limits on measurements can be routinely surpassed.”
Scientist Dr Xu Chen, also from UWA, said OzGrav and their collaborators were able to smash through the quantum noise barrier of gravitational-wave detectors. “At UWA, we aim to improve the sensitivity further with a white-light cavity.
This works best at higher frequencies where we can see more binary neutron stars colliding,” she said.