Controllable Nonclassical Correlation by an Incoherent Pumping Field in a Λ‐Type Atom‐Cavity System

Abstract

It is important to generate stable nonclassical correlation and wide‐band quantum field in quantum optical communication. In this paper, a scheme is proposed to manipulate the nonclassical intensity correlation of two output fields by a coherent coupling laser and an incoherent pumping field. The core of the scheme is that the coherent field is applied to manipulate the intracavity polaritons, and the incoherent pumping field is used to control the linear absorption and the atomic coherence. With the incoherent field, atoms are repopulated on the excited state false|3false⟩$|3\rangle$. It induces a wide‐band zero absorption of a probe field and the negative dispersion that can be used to realize a white‐light cavity. In addition, with the increasement of the incoherent pumping rate, the wide‐band maximum stable intensity correlation and the nonclassical field with sub‐Poissonian distribution are attained, which is verified by the evolution of the second‐order correlation of two output channels.