Experimental demonstration of electrically controllable photonic crystals at centimeter wavelengths

Electrically controllable photonic crystals have been fabricated by inserti ng p-i-n diodes in two-dimensional metallic lattices. A first structure use s a square lattice of thin and discontinuous metallic wires. A second struc ture is fabricated using stacks of printed circuits with metallic strips. T he p-i-n diodes are soldered along the different metallic wires or strips. The crystals have been characterized between 1 and 20 GHz. We show that the y can be operated as wideband switchable electromagnetic windows with high transmission or reflection contrast between on and off states. A similar to 25 dB transmission modulation is reported within the first transmission ba nd of a two-period crystal. We also show that the switching domain and modu lation rate can be varied with a separate bias control for each crystal pla ne. Finally, the distance between crystal planes is used to tune the operat ing frequency range. (C) 1999 American Institute of Physics. [S0003-6951(99 )02337-2].