The optical storage medium comprises a substrate layer, a read-only data layer with a pit structure disposed on the substrate layer, a cover layer and a nonlinear layer with a super-resolution structure disposed between the data layer and the data layer, which super-resolution structure includes a semiconductor material and grainy impurities of a dielectric material, wherein the semiconductor material has an increased reflectivity, when irradiated with a laser beam, and wherein the dielectric material is arranged as a dielectric layer having a thickness below 5 nm. The dielectric material consists advantageously of an inhomogeneous layer of a nitride material, for example GeN, arranged between a first and a second nonlinear layer.