Tunable negative-index photonic crystals using colloidal magnetic fluids*
Geng Tao†, Wang Xin, Wang Yan, Dong Xiang-Mei
       
Normalized average intensities of a point source with f = 0.44 located at 0.65 λ from the PC slab lens at (a) H = 150 Oe with h = 3 a , (b) H = 250 Oe with h = 3 a , and (c) H = 250 Oe with h = 4 a . In panels (a), (b), and (c), the solid lines show the position of the PC slab lens. The z positions of the images are marked by the dashed lines.