White light cavity via modification of linear and nonlinear dispersion in an N-type atomic system

We have experimentally realized a white light cavity (WLC) in a wide range of the cavity input field's intensity in an N-type atomic system. As the linear and nonlinear dispersion can be tuned conveniently, for different cavity input field's intensity, the condition of WLC can be satisfied. In our experiment, the WLC with broad linewidth of about 100 MHz can be achieved with the cavity input field's intensity from a few μW to dozens of mW. This can be applied in the gravitation wave detectors, pulse shaping, nonlinear spectroscopy, atom and ion cooling, etc.