QUANTUM LIGHT VIA RYDBERG EXCITONS

Work package:
This interdisciplinary internship project (chemistry-physics) aims to advance the state of the art in the creation and use of emerging synthetic quantum materials. In particular, cuprite (Cu2O) is a remarkable semiconductor that presents excitons (bound electron-hole pairs) of gigantic size (> 1000x larger than normal), called "Rydberg excitons". By analogy with their atomic cousins (Rydberg atoms) and their many successes for quantum technologies, Rydberg excitons represent an emerging platform with high potential for producing quantum devices integrated into a semiconductor. However, currently only natural materials are of sufficient purity for such devices. These natural crystals are hard to structure and increasingly rare. Finding a chemical synthesis route to synthesize high-purity artificial Cu2O, which can also be structured at will, is therefore a major challenge for quantum technologies based on Cu2O . The objective of this multidisciplinary chemistry-physics internship will be to explore two routes for the synthesis of Cu2O. The first is based on the direct growth of Cu2O microcrystals in hydrothermal conditions (synthesis in high-pressure aqueous media). These conditions tend to produce crystalline particles with well-defined exposed facets. In parallel, initial tests will be conducted on the synthesis of metallic copper nanoparticles using an organometallic approach. This method, developed in the team, allows for an extremely compact copper deposit. A controlled oxidation treatment will then be conducted to reach the targeted Cu2O phase. The crystals/particles obtained by these two methods will be characterized by electron microscopy and X-ray diffraction.