LIGO Instruments/Quantum
The Laser Interferometer Gravitational-wave Observatory (LIGO) opened the era of gravitational-wave astronomy in 2015, with the first detection of gravitational waves from colliding black holes.
The instruments that enabled this discovery are giant antennas able to measure the tiny displacements induced by a passing gravitational wave using laser light to probe the position of suspended mirrors 4 km apart.
Among the most sensitive displacement sensors ever made, the LIGO detectors rely on state-of-the-art technology to isolate the mirrors from the ground, and mitigate all sorts of disturbances that could mask the gravitational-wave signal. Since MIT Prof. Emeritus Rainer Weiss conceived LIGO in the late 60s, the MIT LIGO group has worked on developing the technology needed to enable the detection of gravitational waves like stable lasers, high quality optical coatings, sophisticated seismic and isolation systems, control systems, and, more recently, quantum optics to circumvent the limitations that the quantum nature of light imposes on LIGO.
The quantum techniques developed for LIGO have a direct impact on a variety of other precision measurements, like laser cooling and trapping of macroscopic objects to enable observation of quantum phenomena in human-scale systems.
A description of the MIT LIGO group research areas around Prof. Matt Evans, Prof. Salvo Vitale, and Prof. Nergis Mavalvala can be found at: https://ligolab.mit.edu/.