A Low Loss Photonic Crystal Waveguide at Millimeter Wave

We have presented a new type of photonic crystal (PC) waveguide in our previous report. The waveguide has a low propagation loss at millimeter wave frequencies compared with an NRD guide, but the PC material is difficult to obtain since a relatively high dielectric constant is required. Therefore, this paper presents another low loss PC waveguide constructed of sintered alumina with a dielectric constant of 8.9 easy to obtain. Though the loss of the PC guide is twice larger than that of the previous PC waveguide, its loss is less than that of an NRD guide and the bending loss is reasonable.