Phase Angle and Effective Second-Harmonic Generation Coefficient in Uniaxial Crystal

In this paper, the calculation formulae of phase angle are given for two classes of largest effective SHG coefficients in uniaxial crystals by means of the optimization theory. With the help of such calculation formulae, we present the best phase angles and azimuth angles of all uniaxial crystals class, as well as their effective SHG coefficients. Furthermore, these calculation is only dependent upon some principal subtensor of second order susceptibility tensor.