THz cutoff frequency and multifunction Ti 2Ba2Ca2Cu3O10/GaAs photonic bandgap materials

By using the transfer matrix method (TMM), we theoretically explore the transmittance properties and cutoff frequency of one-dimensional photonic crystal (1DPCs) within the terahertz frequency region. The present structure consists of high-temperature superconductor and semiconductor layers. The results of the calculations represent the effects of various parameters on the cutoff frequency. We have used the two-fluid model as well as the Drude model to describe the permittivity of superconductor and semiconductor. Further, we consider that the permittivity of both the materials is depending on the hydrostatic pressure. The present results show that with the increasing of different parameters as the operating temperature, the thickness of semiconductor, and the filling factor of semiconductor, then the cutoff frequency shift to lower frequencies regions. By the increasing of superconductor thickness, hydrostatic pressure, doping concentration and filling factor of the superconductor, we found the cutoff frequency shifts to higher frequency regions. These results indicate that cutoff frequency can be modified through these different parameters. Finally, the present design could be useful for many optical systems as the optical filter, reflector and photoelectronic applications in the Terahertz regime.

Enhanced sensing in mixed porous–solid photonic stacks

A mix-and-match sol–gel deposition method allows fabrication of one-dimensional photonic bandgap materials with strategically placed porous layers.