Heterodyne non-demolition measurements on cold atomic samples: towards the preparation of non-classical states for atom interferometry

摘要

We report on a novel experiment to generate non-classical atomic states viaquantum non-demolition (QND) measurements on cold atomic samples prepared in ahigh finesse ring cavity. The heterodyne technique developed for the QNDdetection exhibits an optical shot-noise limited behavior for local oscillatoroptical power of a few hundred \muW, and a detection bandwidth of several GHz.This detection tool is used in single pass to follow non destructively theinternal state evolution of an atomic sample when subjected to Rabioscillations or a spin-echo interferometric sequence.