Recycling for a cleaner signal

Observation of gravitational waves, the ripples in spacetime emitted by violent cosmic events such as the deaths of stars and the births of black holes, could revolutionize our understanding of astrophysics. Several groups are engaged in attempts to build gravitational-wave observatories based on advanced laser interferometers. Efforts at this frontier have spawned new techniques, such as light recycling and the use of squeezed light to maximize the detectors' sensitivity. A new tool, called dual recycling, has been demonstrated which allows more efficient use of laser light and provides an elegant method of tailoring the bandwidths of these detectors