Numerical resolution for plane waves in uniaxial blocks

LILIANA INÉS PEREZ; EDUARDO OMAR ACOSTA; CARO GERMÁN EDUARDO

San Miguel de Tucuman

Congreso; Argencon 2018; 2018

It is well known that real birefringent media and interfaces that involve these kinds of media present peculiar characteristics as double refraction, double angle of total reflection, inhibited reflection, phase shift in refraction, etc.. Other two curious phenomena are those called backward wave and negative refraction. The backward wave phenomenon is only related to the backward of the wave number vector and not to the backward of the direction of propagation of energy while in negative refraction the incident and refracted rays are contained in the same half-plane with regard to the normal to the interface. Furthermore, these two phenomena show clearly that the importance of the wave number vector lies fundamentally in the simplicity of their use as a mathematical tool but it can lose physical sense in frequent conditions for uniaxial or biaxial prisms, layers or blocks.In previous works we analysed the conditions necessary for negative refraction and backward wave phenomena to be produced on real dielectric non-magnetic isotropic-uniaxial and biaxial crystal interfaces. The analyses were based on the geometric description of the extraordinary ray and its relationship with the extraordinary wave number vector. The proposed vectorial method allowed us to make a completely analytical calculus for both phenomena for every orientation of the optical axis with regard to the plane of incidence. Nevertheless, we have not taken in account the amplitude and intensity of the involved fields. In this work we present the development of software that can determine direction of propagation, phase and amplitude of each of the waves involved in the propagation, reflection and refraction in birefringent blocks (limited in all directions). As in birefingent media the direction of the normal to the wavefront does not coincide with the direction of propagation of energy, our results are 3D. The software is based on the numerical resolution of exact Maxwell?s Equations. We compare the numerical results for some situations where there is an analytical solution.