The present disclosure provides methods, articles, and apparatuses related to altering electromagnetic radiation. A method of making articles includes a) forming an electromagnetic radiation altering material by providing a polymer matrix and optionally embedding dielectric particles in the polymer matrix and b) obtaining initial dielectric properties of the electromagnetic radiation altering material. The method further includes c) modeling electromagnetic radiation altering features of the material suitable for the article obtained from the material to have target electromagnetic radiation altering properties, thereby obtaining a simulation of the electromagnetic radiation altering article; and d) additive manufacturing the electromagnetic radiation altering article based on the simulation of the electromagnetic radiation altering article. An electromagnetic radiation altering article obtained by the method is also provided. Further, an apparatus is provided including the electromagnetic radiation altering article. Methods of altering electromagnetic radiation are provided, including integrating an electromagnetic radiation altering article into either an electronic device or an electromagnetic radiation producing device, or placing the article in the vicinity of the device. Aspects of the present disclosure advantageously contribute to achieving optimized materials and designs for electromagnetic radiation altering articles.