Tunable photonic crystal filter with dispersive and non-dispersive chiral rods

Applying the finite element method, microcavity photonic crystal filter with chiral rods is studied and tuning of its bandwidth and transmission peak under system's stability condition is discussed. In order to study the tunability of this structure, the effects of variation in its rods electromagnetic parameters on its filtering operation are analyzed. It is shown that the increase in the rods' relative permittivity cause the increase of bandwidth and transmission peak, and also decrease the photonic band gap width. On the other hand, the increase in the rods' relative permeability cause the decrease of bandwidth and transmission peak, and also increase the photonic band gap width. In both cases, peak wavelength red shift occurs. The effects of rods chirality on filtering characteristics are studied. The real and imaginary terms of chirality is introduced respectively as a cause for worsening and bettering filtering nature of chiral photonic crystal, while they do not have effect on peak wavelength and photonic band gap. The effect of dispersive chirality model parameters on structure filtering is discussed and a design of chiral photonic crystal filters with appropriate high peak amplitude and small bandwidth in optical integrated circuits is proposed. (C) 2013 Elsevier B.V. All rights reserved.