Modeling of femtosecond pulse propagation inside x-cut and z-cut MgO doped LiNbO3 anisotropic crystals

Abstract

A four-dimensional spatiotemporal nonlinear Schrödinger equation coupled with a plasma equation is solved for anisotropic crystal of MgO doped lithium niobate. The modeling is performed for x-cut and z-cut lithium niobate crystals commonly used for waveguide writing by femtosecond lasers. The effect of various parameters such as energy, duration, and polarization of the incident laser pulse on distribution of the plasma density in the vicinity of focus is studied. Our simulations reveal that the maximum plasma density in the vicinity of the focus is higher for longer pulse durations and higher pulse energies. Furthermore, it is observed that for the same peak powers of the incident pulse, the plasma density generated inside the crystal is higher for linear polarization as compared to circular polarization.