Effects of pump depletion on spatial and spectral properties of parametric down-conversion

摘要: It is well known that optical twin-beam states (TWB) generated by spontaneous parametric down-conversion (PDC) exhibit spatial and spectral correlations, which can appear in single-shot images obtained using an imaging spectrometer to resolve emission angles wavelengths simultaneously. By analyzing series of recorded EMCCD camera at different powers the pump beam, we studied evolution several quantities characterizing TWB. In particular, demonstrated correlation widths spectrum space increase monotonically low then start decreasing higher due onset depletion. a complementary way, Fedorov ratio decreases increases again. At same time, number modes evaluated from photon statistics follows behavior be interpreted terms Schmidt field.