Giant negative Goos-Hänchen shifts for a photonic crystal with a negative effective index.

The Goos-Hänchen effects are investigated for a monochromatic Gaussian beam totally reflected by a photonic crystal with a negative effective index. By choosing an appropriate thickness for the homogeneous cladding layer, a giant negative GH lateral shift can be obtained and the totally reflected beam retains a single beam of good profile even for a very narrow incident beam. The GH lateral shift can be very sensitive to the change of the refractive index of the cladding layer, and this property can be utilized for e.g. the switching applications.