Quantum-jump telegraph noise and macroscopic intensity fluctuations

Abstract

We examine the intensity fluctuations in the fluorescence from a single three-level atom exhibiting quantum jumps. The macroscopic intensity fluctuations revealed in the quantum random telegraph signal of emitted light are the signature of transitions between rapidly emitting and metastable states. We calculate the Mandel Q parameter for such a three-level atom both for incoherent and coherent driving and demonstrate how it provides a sensitive measure of the jumps. We show that the Q parameter reflects the existence of periods of brightness and darkness in the telegraph signal more directly than the second-order intensity correlation function.