Photonic crystals of coated metallic spheres
FOM Institute AMOLF - Kruislaan 407, 1098 SJ Amsterdam, The Netherlands
Accepted: 15 March 2000
It is shown that simple face-centered-cubic (fcc) structures of both metallic and coated metallic spheres are ideal candidates to achieve a tunable complete photonic bandgap (CPBG) for optical wavelengths using currently available experimental techniques. For coated microspheres with the coating width to plasma wavelength ratio and the coating and host refractive indices and , respectively, between 1 and 1.47, one can always find a sphere radius such that the relative gap width (gap width to midgap frequency ratio) is larger than and, in some cases, can exceed . Using different coatings and supporting liquids, the width and midgap frequency of a CPBG can be tuned considerably.
PACS: 42.70.Qs – Photonic bandgap materials / 82.70.Dd – Colloids / 42.70.Nq – Other nonlinear optical materials; photorefractive and semiconductor materials
© EDP Sciences, 2000