Diamagnetic response of metallic photonic crystals at infrared and visible frequencies

We show analytically and numerically that diamagnetic response (effective magnetic permeability mu(e) < 1) at infrared and visible frequencies can be achieved in photonic crystals composed of metallic nanowires or nanospheres when the wavelength lambda is much larger than the lattice constant a (lambda similar to 2000a). When lambda similar to 100a, the metallic photonic crystals will exhibit strong diamagnetic response (mu(e) < 0.8), leading to many interesting phenomena such as the unusual Brewster angle for s waves and incident-angle-and-polarization-independent reflection and transmission.