Interferometry in a strong light

Event Dates: 

Wednesday, September 23, 2015 - 4:00pm

CTQM Seminar Type: 

  • Related Seminar Series

Speaker Name(s): 

Cindy Regal

Speaker Affiliation(s): 

University of Colorado Boulder

Abstract, Event Details: 

The best rulers are made from light!  Optical interferometry is at the heart of many precise measurements from gravitational wave searches to modern surface diagnostics and microscopy.  Generally one improves interferometer precision by increasing the light intensity, as well as by calming the many technical sources of noise that can perturb the mirrors or optical path.  However, at extreme levels of light strength where radiation forces are significant, a new and interesting disturbance should appear – the quantum shaking associated with random arrival of individual photons at a mirror of the interferometer.  This quantum backaction of light has been long foreseen in gravitational wave searches and played a formative role in quantum optics theory.  In this talk I will discuss an experiment in which we used a particularly compliant micro-scale, vibrating drum to finally observe this effect in an interferometer.  In this strong-light limit, interferometer mirrors can also be used as a nonlinear medium to manipulate light – for example to make squeezed light.  We are pursuing ways to translate more complex quantum states into light by coupling superconducting elements to an interferometer mirror.