Band Structures Of Two-dimensional Photonic Crystals Research Articles

Temperature dependent complex photonic band structures in two-dimensional photoniccrystals composed of high-temperature superconductors

Complex photonic band structures in two-dimensional photonic crystalscomposed of high-temperature superconductors (HTSCs) for the case ofE-polarization are calculated as a function of temperature belowTc,where Tc is the critical temperature of the HTSC. The calculations are based on a temperaturedependent complex dielectric function, which includes contributions of both superconductingelectrons (SCEs) and normal conducting electrons (NCEs), and a frequency dependentplane wave expansion method. Both temperature independent and temperature dependentdamping term in the dielectric function are considered to calculate dispersion relations andthe lifetime of the eigenmodes. The results are compared with those obtained by existingcalculation methods, which neglect the contribution of NCEs. Our results correspond quitewell with those obtained by the existing method in the low-temperature range0<T/Tc≤0.3; however, results obtained with the two methods are quite different in the temperature range0.3<T/Tc≤1. We demonstrate that the contribution of NCEs is non-negligible with increasingtemperature.

Properties of two-dimensional photonic crystals with octagonal quasicrystalline unit cells

The bandstructures of two-dimensional photonic crystals with octagonal quasicrystalline unit cells have been calculated. The existence of photonic band-gaps in such structures is demonstrated, and results showing the variation of the spectral position and width of the photonic band-gaps with the size of the unit cell and filling fraction within the unit cell are presented.