Heisenberg limited Sagnac interferometry
arXiv:0705.2468 · doi:10.1364/OE.15.006798
Abstract
We show how the entangled photons produced in parametric down conversion can be used to improve the sensitivity of a Sagnac interferometer. Two-photon and four-photon coincidences increases the sensitivity by a factor of two and four respectively. Our results apply to sources with arbitrary pumping and squeezing parameters.
11 pages, 5 figures