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We have fabricated a layered nano-composite by alternating metal and gainmedium layers, the gain dielectric consisting of a polymer incorporatingoptically pumped dye molecules. Exploiting an improved version of the effectivemedium theory, we have chosen the layers thicknesses for achieving a very smallvalue of the real part of the permittivity epsilon_\| (parallel to the layersplane) at a prescribed visible wavelength. From standardreflection-transmission experiments on the optically pumped sample we showthat, at a visible wavelength, both the real and the imaginary parts of thepermittivity epsilon_\ attain very small values and we measure | \epsilon_\| |= 0.04 at lambda = 604 nm, amounting to a 21.5-percent decrease of the minimum| \epsilon_\| | in the absence of optical pumping. Our investigation thusproves that a medium with a dielectric permittivity with very small modulus, akey condition which should provide efficient subwavelength optical steering,can be actually synthesized.

Gain assisted nanocomposite multilayers with near zero permittivity modulus at visible frequencies