A simulation program for the study of response of arbitrary photonic media

ANDRÉS E. DOLINKO

Ciudad de Buenos Aires, Argentina

Congreso; NFO10, the 10th International Conference on Near-field Optics, Nanophotonics and Related Techniques; 2008

Universidad de Buenos Aires

The technology of devices based in photonic crystals is one of the fastest growth. As in solidstate physics, photonic crystals are based in the theory of band gaps where the photons in this kind of medium play the same role as the electrons in the atomic crystal lattice. A photonic crystal is normally a periodic structure formed of a transparent dielectric material with different refraction index distributions. If the spacing between the discontinuities in the refractive index is comparable with the wavelength, the propagation of light waves within the lattice is subject to conditions similar to those of X-rays propagating in a crystal lattice. This allows obtaining different effects that are used as Bragg filters or wave-guides in the form of optical fibers made of photonic crystals. Photonic structures with random distribution of refraction index are also greatly study. In this case, the photonic medium behave like a diffusive medium and the possibility of continuously varying the complexity of a structure from a high disordered state to an ordered one and from simple scattering to a resonant scattering opens the possibility to the development of totally new photonic devices. A suitable way to study these kinds of complex nano-structures is by means of computer simulations. In this work, we present a simulation program that allows studying the propagation of electromagnetic radiation in a medium with arbitrary refractive index geometries. The program is based on the numerical solution of the electromagnetic wave equation derived from the Maxwell equations with the presence of sources. The wave equation is solved by means of the method of finite differences and allows tracking the evolution of the electromagnetic wave as a function of time through the photonic medium in real time, running on a conventional personal computer. Since the characteristics of the medium, such as its electric permitivity or magnetic permeability, are easily feed to the program, it allows studying the response of a great number of complex photonic structures. Several results on known examples of nano-photonic devices are presented, showing the ability of the proposed method to predict the response of new photonic structures.