Physical Review A
Light controlling light in a coupled atom-cavity system
Bichen Zou, Yifu Zhu
Abstract
We present a theoretical study of a multiatom cavity quantum electrodynamics system consisting of three-level atoms confined in a cavity and interacting with a control laser from free space. A probe laser is coupled into the cavity, and the transmitted cavity field and reflected probe field from the cavity are analyzed. We show that the free-space control laser induces large nonlinearities for the intracavity probe field, which can be used to control the amplitude and phase of the reflected probe light and the transmitted probe light. Under appropriate conditions, large cross-phase modulation for the reflected and transmitted light fields can be obtained with a weak control field, which renders the system useful for studies of all-optical switching and quantum phase gates.