Electronic transitions and fermi edge singularity in polar heterostructures studied by absorption and emission spectroscopy
| Autor: | Anna Cavallini, Piero Gamarra, Beatrice Fraboni, Daniela Cavalcoli, Albert Minj, Saurabh Pandey, M. A. Poisson |
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| Přispěvatelé: | S. Pandey, D. Cavalcoli, Minj, Fraboni, Cavallini, P.Gamarra, M. A. Poisson |
| Jazyk: | angličtina |
| Rok vydání: | 2012 |
| Předmět: |
FERMI EDGE SINGULARITY
Materials science Photoluminescence Condensed matter physics Surface photovoltage Fermi level General Physics and Astronomy SURFACE PHOTOVOLTAGE Fermi energy Heterojunction Condensed Matter::Mesoscopic Systems and Quantum Hall Effect symbols.namesake Condensed Matter::Materials Science symbols INALN/ALN/GAN STRUCTURES Emission spectrum Spectroscopy Absorption (electromagnetic radiation) |
| Popis: | Optically induced electronic transitions in nitride based polar heterostructures have been investigated by absorption and emission spectroscopy. Surface photovoltage (SPV), photocurrent (PC), and photo luminescence spectroscopy have been applied to high quality InAlN/AlN/GaN structures to study the optical properties of two dimensional electron gas. Energy levels within the two dimensional electron gas (2DEG) well at the interface between the GaN and AlN have been directly observed by SPV and PC. Moreover, a strong enhancement of the photoluminescence intensity due to holes recombining with electrons at the Fermi Energy, known as fermi energy singularity, has been observed. These analyses have been carried out on InAlN/AlN/GaN heterojunctions with the InAlN barrier layer having different In content, a parameter which affects the energy levels within the 2DEG well as well as the optical signal intensity. The measured energy values are in a very good agreement with the ones obtained by Schrodinger–Poisson simulations. |
| Databáze: | OpenAIRE |
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