Three Dimensional Plasma Photonic Crystals: Tunable Bandstop Filters Comprising Microplasma Column Arrays

We demonstrate 3D microplasma photonic crystals (3D MPPC) as tunable filters in the 120 - 170 GHz region. Comprising 355 μm diameter columns of low temperature plasma, these photonic crystals have a staggered log pile geometry and are capable of being reconfigured electronically. For one crystal design, the attenuation at 138 GHz is increased, by 12 dB when the microplasma array is activated. The presence of plasma also increases the Q of several resonances to > 2000. The ability to control three-dimensional arrays of microplasma columns in compact (~ 100/mm
³
) polymer structures offers enormous versatility for microwave devices and communications systems.