PHOTONIC BAND-GAPS IN BODY-CENTERED-CUBIC STRUCTURES

Photonic energy bands in body-centered-cubic bcc materials are analyze d by considering structures having O8 (I4(1)32) space-group symmetry. Such structures can be realized physically by interlacing cylindrical elements oriented along [111] crystallographic axes. In addition to he terogeneous systems composed entirely of dielectric materials, the pos sibility of using conducting materials (particularly at microwave freq uencies) is studied. We find that (a) band gaps occur in heterogeneous dielectric systems when materials having a dielectric constant of 10 or more are properly placed in the O8 unit cell, and (b) utilizing con ducting materials can significantly widen the excluded frequency band, the result being that band gaps of more than 20% should be attainable with O8 structures at microwave frequencies. Experimental verificatio n of these results should be possible in this spectral region.