Superbunching pseudothermal light with intensity modulated laser light and rotating groundglass

Pseudothermal light by scattering laser light from rotating groundglass has been extensively applied to study optical coherence in both classical and quantum optics since its invention in the 1960s. In this paper, we will show that by replacing the intensity invariant laser light in pseudothermal light source with intensity modulated laser light, superbunching pseudothermal light can be obtained. Two-photon superbunching is experimentally observed by employing common instruments in optical laboratory. Two-photon interference in Feynman's path integral theory is employed to interpret the results. The proposed superbunching pseudothermal light is helpful to understand the physics of two-photon bunching and superbunching.