Analysis of Photonic Band Structure Tunability for TE and TM Modes in a Silicon and Polymer Based Ternary Photonic Crystal for Visible Range Devices.

In this paper, we report on the tunable dispersion characteristics of TE and TM modes in a ternary PPC comprised of graphene, silicon and polymer as nanolayers. By employing TMM, it is investigated that the structure shows novel ideas of tunability with the variations in the incident angle and polymer thickness in which Bloch waves are affected. The polymer-based 1D TPC exhibits two forbidden gaps, while the focus of illustration is on the wideband located in higher wavelength region for both TE and TM polarizations. With increase in the incident angle, the two PBGs show a blueshift in both cases of TE and TM modes, whereas with increase in the polymer thickness, the PBGs of TE waves show a reverse effect, viz. redshift. Further, the enlarged forbidden gap slightly increases in width for TE polarization, whereas in the case of TM polarization, it is decreasing drastically. The shifting in the position towards low wavelength for upper bandedge is more effective in the TM mode as compared to that of the TE mode. By increasing the polymer thickness, the gap also increases for TE mode. The 3D reflection spectra for s and p waves show that, a PBG of width 40 nm in the wavelength range 555.6–595.6 nm, is common in the enlarged PBG for both TE and TM modes, and so the TPC bears the features of ODR in the visible region. Such novel features of tunablity can be useful in designing optical devices in the visible region, including broadband reflectors, narrowband ODRs, and low-loss perfect reflectors for solar cells. [ABSTRACT FROM AUTHOR]