Lasers support certain structures of light known as “eigenmodes.” An international collaboration of experts in gravitational waves, metasurfaces, and photonics has pioneered a new method to measure the amount of these eigenmodes with unprecedented sensitivity.
In gravitational wave detectors, several pairs of mirrors are used to increase the amount of laser light stored along the massive arms of the detector. However, each of these pairs has tiny distortions that scatter light away from the perfect shape of the laser beam. This scattering can cause excess noise in the detector, limiting sensitivity, and ultimately forcing the instrument to shut down.
