Periodic photonic bandgap crystal (PBC) structures channel electromagnetic waves much as semiconductors/quantum wells channel electrons. PBCs are fabricated by arranging sub-wavelength alternating materials with high and low dielectric constants to produce a desired effective bandgap. Photons with energy within this bandgap cannot propagate through the structure. This property has made these structures useful for microwave applications such as frequency-selective surfaces, narrowband filters, and antenna substrates when the dimensions are on the order of millimeters. They are also potentially very useful, albeit much more difficult to fabricate, in the visible/infrared region for various applications when the dimensions of the substrate range from 40 nm to 4000 nm. We intend to micro-fabricate suspended free standing micro-structure substrates with dimensions from 2 to 100 micrometers in length. Extremely high resonance (~ 10 GHz) frequencies are possible with very small dimension MEMS. Nanoscale periodic structures would be fabricated onto these micro-structure substrates to form a tunable system. If this combined structure is perturbed, such as mechanical deflection of the suspended composite structure at resonance, there will be a substantial and realtime shift in the material effective bandgap due to the periodicity alteration. This active device capability would present numerous applications in the opto-electronic /integrated optic fields if the feasibility of dynamic tuning could be demonstrated.
