Nanostructured gallium oxide for photonics

The Physics of Electronic Materials Group (FINE Group) is a consolidated research team composed by 9 researchers as staff members and 5 PhD students, which has been working steadily on the study of optical and electronic properties of semiconductors by means of electron microscopy and optical spectroscopy techniques for more than 25 years. Ohe of the main research lines in the group is focused on Semiconductor nanostructures: physical properties and applications. We have been involved in several international projects, such as a Marie Curie Training Site and TPVCell European Training Network (ETN); Bilateral actions with Germany, Portugal, Italy and France. We are currently working on a national project related to functional wide band gap nano-oxides, an AFOSR (USA) project on gallium oxide and an H2020 European project, devoted to batteries. The FINE Group manages its own facilities at the UCM premises to carry out experimental research on an independent basis. The main equipment consists of four scanning electron microscopes (SEM) with advanced techniques as cathodoluminescence (CL), electron backscatter diffraction (EBSD) or energy dispersive X-ray microanalysis spectroscopy (EDS) to study structural and optical properties. A high-resolution spectrofluorimeter with a closed-cycle He cryostat, an optical confocal-Raman microscope and an AFM complete the battery of equipment for materials characterization. Its infrastructure enables a very thorough material science research.

The scope of the research activity is the study of semiconductor nanostructures, especially those based on the ultra-wide bandgap gallium oxide, with the aim to investigate their structure, morphology and physical properties, mainly oriented to photonics applications. We have developed a synthesis route that enables us to get reproducible nanomaterials with different morphologies (nanowires, nanorods, nanobelts, hierarchical structures, complex nano-heterostructures,...) based on a thermal evaporation method. In addition, a full characterization of the obtained nanomaterials is carried out in the group premises. We study the local properties of the obtained nanostructures with high spatial resolution with the aid of, but not only, electron microscopy and optical spectroscopy related techniques.
The current projects, entitled "Exploring light-matter interaction in gallium oxide micro- and nanostructures" and “New paradigms in wide bandgap functional nano-oxides. In-situ characterization and microscopy”, aim to optimize the optical and electrical properties of of the nanostructures. We tune the physical properties in several ways: doping (optically active impurities, carrier concentration); morphology (branched structures, photonic artificial structures, optical cavities…); and dimensionality (hybrid structures with nanowires/ultrathin films) of the oxide based nanostructures.

Interested applicants should submit to the Contact Person (see above) a motivation letter, a recent Curriculum Vitae and two reference letters. The motivation letter should list the names of the researchers who give the reference letters.