Calculation of Excitonic Absorption Spectrum of GaAs Quantum Wire Free-Standing in Vacuum |
| P. Vagnera, D. Munzarb and M. Moškoa aInstitute of Electrical Engineering, Slovak Academy of Sciences, Dúbravská cesta 9, 842 39 Bratislava, Slovak Republic bDepartment of Solid State Physics, Faculty of Science Masaryk University, Kotlářská 2, 611 37, Czech Republic |
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| The electron-hole interaction in a thin (≈10 nm) GaAs quantum wire free-standing in vacuum is strongly enhanced by the image charge due to the abrupt permittivity drop at the wire surface. As a result, the exciton binding energies are much larger and the exciton wave functions much more localised than those of the GaAs quantum wire surrounded by the AlGaAs. The absorption spectrum of the free-standing wire shows besides the 1s exciton peak also the 3s and 5s exciton peaks, even if the peaks are 15 meV broad. The continuum absorption edge shows a large blue shift due to the renormalization of single-particle energies by the image charge. |
| DOI: 10.12693/APhysPolA.92.1038 PACS numbers: 73.20.-r, 73.20.Dx |