Photon counting statistics of a single molecule under pump–probe fields

We consider the photon statistical properties emitted from a two-level quantum system under pump–probe driving. The line shapes and Mandel's Q parameters are studied for a single quantum system based on the generating function method developed recently. The control of photon emission from a single quantum system driven simultaneously by a driven field and a tunable probe field is investigated. Our theoretical results and the experimental results are in good agreement. (paper)