Skip to main content

Interferometer Sensing and Control in Gravitational Wave Detectors


Interferometer Sensing and Control in Gravitational Wave Detectors

Hosted By: Photonic Detection Technical Group

15 October 2019, 14:00 - 15:00

Download Presentation Slides

In this webinar hosted by the OSA Photonic Detection Technical Group, Dr. Lee McCuller of the LIGO Laboratory at MIT will briefly describe the generation and detection of gravitational waves from astrophysical sources and of the science it enables. He will introduce the noise-spectrum and how it affects time-domain detection of gravitational-strain signals. In addition, the fundamental displacement phase sensitivity of light and improvements/tradeoffs that cavity-enhancement brings to Michelson interferometers will be discussed.

An overview of the instrument requirements for desirable acoustic-frequency sensitivity and influence of experimental design will be provided that touch upon the need for RF-interferometric sensing, relating to fundamental optical sensitivity, including the effects of using additional frequencies interacting with the cavities to discriminate degrees of freedom. Core optics, beam jitter, laser amplitude noise stabilization, and frequency stabilization of the laser (Pound-Drever-Hall sensing) will be briefly discussed. These may then be generalized to sense other degrees in the interferometer, including "wavefront sensing" alignment sensing though RF modulations. Radiation-pressure induced optomechanics as related to quantum mechanics with a simple phase-space description and how squeezing enhances sensitivity and interacts with the optomechanics, with some brief notes of its implementation in a large-scale experiment, will be discussed. 

What You Will Learn:

  • Basics of gravitational waves
  • Overview of LIGO's requirements 
  • RF optical sensing techniques and the technology behind the groundbreaking gravitational wave detection 

Who Should Attend:

  • Scientists 
  • Engineers

About the presenter

Lee McCuller, LIGO Laboratory, MIT
Lee McCuller, LIGO Laboratory, MIT Image

Dr. Lee McCuller is a research scientist with the LIGO laboratory group at MIT. He works on frequency dependent squeezed light to enhance gravitational wave interferometers. He is particularly interested in modeling and quantum-limited control of optomechanical systems. In 2015, the Laser Interferometers Gravitational-wave Observatory (LIGO) made the first direct detection of the gravitational field emission from the coalescence of a binary black hole system. This feat of astrophysical observation was accomplished using a 4km optical interferometer sensitive at acoustic frequencies. Dr. McCuller graduated from the University of Chicago in 2015 with a Ph.D. in Physics, advised by Prof. Stephan Meyer, and has since been a part of the LIGO team at MIT.