Abstract
The linear and nonlinear dispersion and absorption properties of a Y-type four-level system, which driven by a weak probing field and two coupling fields, are investigated. Using the perturbation method, third-order perturbation iterative solutions of the steady density matrix equations are obtained. Numerical results and the analysis with the dressed state show that when the two coupling fields are in two-photon resonance, the dispersion and absorption spectra are symmetrical, there is only one transparency window in the system. When the two coupling fields are off two-photon resonance, the dispersion and absorption spectra are no longer symmetrical, and there are two transparency windows in the system. The third-order nonlinear properties of the system are mainly determined by the population difference between the levels which associate with the probing field, and the contributions of the transitions associated with the coupling fields are negligible.
Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callMore From: Optik - International Journal for Light and Electron Optics
Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
