VLADIMIROVA , M.

Les fluides quantiques d'excitons indirects sont un système bosonique intéressant en tant qu'état collectif quantique de longue durée de vie. Nous présentons les progrès récents pour leur génération, leur refroidissement et leur piégeage dans des puits quantiques GaN/(Al,Ga)N, ainsi que les premières indications de condensation dans un état...

GaN/AlxGa1−xN quantum wells were grown by molecular beam epitaxy on high quality bulk (0001) GaN substrates. The quantum well thickness was set in the 6–8 nm range to favor the photoluminescence emission of indirect excitons. Indeed, such excitons are known to be spatially indirect due to the presence of the internal electric field which...

The Mott transition from a dipolar excitonic liquid to an electron-hole plasma is demonstrated in a wide GaN/(Al,Ga)N quantum well at $T=7$K by means of spatially-resolved magneto-photoluminescence spectroscopy. Increasing optical excitation density we drive the system from the excitonic state, characterized by a diamagnetic behavior and thus a...

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Excitons hosted by GaN/(Al,Ga)N quantum wells (QWs) are spatially indirect due to the giant built-in electricfield that separates electrons and holes along the growth direction. This electric field, and thus exciton energy,can be reduced by depositing metallic layers on the sample surface. Using spatially resolved microphotolu-minescence...