Draft:Graciani interferometer



The Graciani interferometer or 3D stochastic interferometer is an amplitude-splitting interferometer operating upon a volume, and a practical realization of the 3D random wave model. introduced by Sir Michael Victor Berry.

The Graciani interferometer is constructed using a Lambertian Ulbricht cavity with high albedo filled with a coherent monochromatic photon gas. This setup creates a statistically isotropic and homogeneous speckle interference pattern sensitive to minute variations of the cavity geometry or the dielectric tensor field within it.

The interferometer operates by measuring intensity fluctuations of a single speckle grain to calculate the frequency spectrum of perturbations. The interferometric response is non-local, not depending on where the perturbation sits nor where the response is measured.

Such instruments can reach Fabry-Perot interferometer equivalent finesses of about 10,500 allowing for picometric measurements of vibrations. Coupled with conventional optical rheology and particle sizing methods such as Dynamic Light Scattering and Diffusing-Wave Spectroscopy, they allow for the amplified measurement of diluted suspensions of colloids and the marker-free study of proteins by light scattering through a technique called Cavity Amplified Scattering Spectroscopy