Squeezed light injection into gravitational wave interferometers
(A) The optical parametric oscillator, designed at ANU and built at MIT, is at the heart of the squeezed light injection system in the 4km, billion dollar Laser Interferometer Gravitational-wave Observatory (LIGO) in the USA. The squeezed light is used to reduce the noise of the vacuum field (zero-point energy) fluctuations below the standard quantum limit. This noise reduction increases the sensitivity of the interferometer to the fluctuations in the fabric of space-time due the gravitational waves. The gravitational waves are produced by asymmetric solar mass objects rotating at significant fractions of the speed of light.
(B) and (C): ANU students at the American site working with LIGO scientists installing the squeezer assembly into the main interferometer assembly.
 K. McKenzie et al, Phys. Rev. Lett. 93, 161105 (2004) (paper)
 S. S. Y. Chua et al, Optics Letters 36, 4680-4682 (2011) (paper)
 M. S. Stefszky et al, Class. Quantum Grav. 29 145015 (2012) (paper)
 A. R. Wade et al, Nature Sci. Rep 5:18052 (paper)