Optical Anisotropy of Non-Cubic Crystal

Analytic formulae for finding the components the complex dielectric tensor of non-cubic crystals are derived Although the method can be applied to the sample with an arbitrary orientation, it is applied to some special cases because of the complexity of the formulae. For uniaxial crystals two cases are discussed in detail； one with the optic axis perpendicular to the reflecting surface and the other with the optic axis in the surface. Both cases have rather simple analytic formulae and can be applied to the real ellipsometric measuremenis. LuNi2B2C sample, whose crystal structure is body centered tetragonal, was measured and the whole complex dielectric tensor was found. The possibilities and the limitations on the real measurements will be discussed.