Nergis Mavalvala

Massachusetts Institute of Technology

Research field

Gravitational wave detectors, quantum measurement

Nergis Mavalvala works on the instruments that detect gravitational waves and on the quantum limits of measurement. Her group at MIT developed squeezed light for LIGO, a state of light with less phase noise than the vacuum allows on its own. The 2019 paper featured here reports the first use of squeezed light during observations, which lowered the noise of both LIGO detectors above 50 Hz and raised the expected detection rate by 40 to 50 percent. The unit uses this work to show how the photon counting limit of an interferometer is overcome.

In the masterclass

Section 1 explains how a laser interferometer measures strain and then presents squeezed light as the way past its photon counting noise.

The research is presented in Unit 16: Frontiers of Astrophysics, in a research spotlight box that explains the result at the level of the unit and links it to the physics you have just learned.

The paper

Quantum-Enhanced Advanced LIGO Detectors in the Era of Gravitational-Wave Astronomy