Diffraction of an ultrashort pulsed beam with arbitrary polarization state from multilayer volume holographic grating in LiNbO3 crystals

Abstract Based on the modified coupled-wave theory of single volume grating and matrix theory, the diffraction properties of multilayer transmission volume holographic gratings (MTVHG) are studied when they are illuminated by ultrashort pulse laser with arbitrary polarization state. The dependences of the diffracted intensity distribution, diffraction bandwidth and the total diffraction efficiency of the multilayer system on the polarization angle of the input ultrashort pulse are investigated. The results show the larger variation range of the spectral bandwidth can be obtained with the thinner thickness of intermediate layer, and the bimodal distribution of the diffracted pulse appears in MTVHG with smaller grating thickness and modulation index compared with the single volume grating. Also, it found that the centers of the diffracted pulses all shift to the positive time-axis, and the displacement becomes larger as the thickness of intermediate layer gets larger, but the displacement almost do not change with the variation of the polarization angle. Results of our study can be valuable for the design and investigation of novel optical devices based on multiple layers of volume holographic grating.