  In this paper, we numerically demonstrate a near-infrared negative-index
metamaterial (NIM) slab consisting of multiple layers of perforated
metal-dielectric stacks and exhibiting low imaginary part of index over the
wavelength of negative refraction. The effective index is obtained using two
different numerical methods and found to be consistent. Backward phase
propagation is verified by calculation of fields inside the metamaterial. These
results point to a new design of low loss thick metamaterial at optical
frequencies.
