The recently introduced coordinate transformation method provides the mathematical foundation for designing electromagnetic "invisibility" cloaks based on a prescribed spatial variation in their constitutive parameters [1-5]. It was demonstrated that by using a reduced set of material parameters for TE/TM incident waves, a cylindrical cloak design would require only one component of permeability/permittivity to be variable in the radial direction, although one undesirable side effect of this simplification is that it resulted in a non-perfect impedance match. The microwave cloak demonstarted in [2] for a TE incident wave was built from a metamaterial consisting of split-ring resonators (SRRs) that provided variable permeability. Moreover, in [4] it was suggested that an optical cloak could be designed from composite layers comprising metal nanowires to provide for permittivity variation under TM excitation. However, losses due to the metallic components employed in these cloak designs should significantly degrade the cloak performance [3], especially at higher frequencies of operation (e.g., infrared and visible). It is, therefore, very attractive to consider all-dielectric metamaterials for application in optical cloaking. The possibility of constructing all-dielectric metamaterials from ceramic dielectric resonators (DRs) for operation at microwave frequencies was demonstrated in [6, 7]. Recently, the properties of chalcogenides have attracted a lot of attention due to their high refractive index and low-loss over a relatively wide spectral range (near- to mid-infrared). For example, chalcogenide glass has been used to fabricate photonic crystals [8]. This paper introduces a design methodology for low-loss optical cloaks that is based on arrays of chalcogenide glass resonators. We employ full-wave electromagnetic simulations to investigate resonance modes of DRs, examine experimentally measured material parameters of available chalcogenide glass, and design resonator configurations and their arrangenment in the cloak for operation in the near-infrared range. Coupling effects in these DR arrays are considered and taken into account.
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