Active light emitting nanostructured materials are essential elements for the development of compact and efficient devices in applications such as photonics, lighting, safety, sensing and biotechnology. These nanostructured materials require a suitable design and specific choice of wavelength depending on the targeted application. Rare-earth(RE) ions are known for providing a robust and high purity light emission Within this context we aim to design and fabricate nanostructured efficient emitters that will be used as building blocks for the development of the next generation of complex photonic devices that will have integrated functionalities such as emission, switching, processing and detection of light, operating in a wide wavelength range covering the visible-infrared spectrum.

 In this talk we will present the recent results obtained by our group using the methodology of embedding nanolayers of rare-earth ions into thin film oxides and oxinitrides with the aim to build efficient nanoemitters. By suitably choosing the nature, composition and crystallinity of the matrix, and the oxidation state of the RE-ion and its concentration and distribution in the nanolayers we will show several examples of functionalized emission. The examples will include the demonstration of narrow emission from pure europium oxide thin films in which fine tuning of the emission is shown by exploiting crystal field effects triggered by stress, the development of efficient wide band emitters in the visible based on Eu²⁺ doped oxide and oxinitride films, and the demonstration of RGB emission based on a combined doping of RE-ions.