Spectral switches of vector Gaussian Schell-model beams passing through a spherically aberrated lens

On the basis of the polarization matrix and propagation equation of the cross-spectral density matrix, the spectral changes for the on-axis spectrum of vector Gaussian Schell-model (GSM) beams focused by a spherically aberrated lens are studied, where the influence of the spherical aberration, correlation and polarizer on the behaviour of the spectral switch is stressed. It is shown that the spectrum of vector GSM beams passing through a spherically aberrated lens may be blueshifted and redshifted in comparison with the source spectrum, and a spectral switch may also take place. However, there are only blue shifts for two kinds of cases passing through an aberration-free lens and an astigmatic lens. The spectral switch arises from the oscillation of the spectral modifier with frequency.