Optical loss compensation in a bulk left-handed metamaterial by the gain in quantum dots

A bulk left-handed metamaterial with fishnet structure is investigated to show the optical loss compensation via surface plasmon amplification with the assistance of the gain medium of PbS quantum dots. Simultaneously negative permittivity and permeability are confirmed at the telecommunication wavelength (1.5 mu m) by the retrieval of the effective electromagnetic property. The dependence of enhanced transmission on the gain coefficient, as well as on the propagation layers, demonstrates that ultralow loss is feasible in bulk left-handed metamaterials.