Alternative Approach to All-Angle-Negative-Refraction in Two-Dimensional Photonic Crystals
Y. J. Huang, W. T. Lu, and S. Sridhar
Phys. Rev. A, V.76, P.013824 (2007)
We show that with an appropriate surface modification, a slab of photonic crystal can be made to allow wave transmission within the photonic band gap. Furthermore, negative refraction and all-angle negative refraction _AANR_ can be achieved by this surface modification in frequency windows that were not realized before in two-dimensional photonic crystals _C. Luo et al., Phys. Rev. B 65, 201104 _2002__. This approach to AANR leads to different applications in flat lens imaging. Previous flat lens using photonic crystals requires object-image distance u + v less than or equal to the lens thickness d, u + v = σd. Our approach can be used to design a flat lens with large σ, thus being able to image large and/or far away objects. Our results are confirmed by finite-difference time-domain simulations.