Study on propagation properties of Gaussian-Schell model beams in negative index medium

In order to study the propagation characteristics of Gaussian-Schell model(GSM) beams in negative index medium, the analytical expression was obtained for the cross-spectral density function of GSM beam passing through negative index medium based on the matrix optics theory, diffraction integral theory and unification theory of coherence and polarization. The spectral density and the spectral coherence degree of the beam passing through the negative index medium were obtained with the formula. Numerical examples show that both the spectral density and the coherence spectral degree of GSM beam can be modulated by the frequency of the negative index medium. The results provide a new modulation method for the beam propagation.