Electron excitation rate in dielectrics under an intense elliptically polarized laser field

Electron excitation in dielectrics is studied for an elliptically polarized laser field. As the first step, we develop an analytical formula for electron excitation rate under elliptically polarized laser as the extension of our previous work [T.Otobe et. al., JPSJ88(2019) 024709]. In the next step, we calculate the excitation rate depending on the band structure by assuming direction dependence of reduced mass. We find that although the ellipticity decreases the excitation rate significantly in an isotropic system, the energy oscillation of electrons due to the intra-band dynamics in the anisotropic band structure increases the excitation rate with higher ellipticity. Our results indicate that we can control the excitation rate in dielectrics by varying the ellipticity, depending on the band anisotropy.