High Magnetic Field Reveals the Nature of Excitons in a Single GaAs/AlAs Core/Shell Nanowire

Paulina Plochocka (1) , Anatolie Mitioglu (1) , Duncan Kennedy Maude (1) , Rikken G.L.J.A. (1, 2) , A. Granados del Aguila , Peter C. M. Christianen (3) , P. Kacman , Hadas Shtrikman (4)

1 LNCMI-T - Laboratoire national des champs magnétiques intenses - Toulouse
2 LNCMP - Laboratoire National des Champs Magnétiques Pulsés
3 Radboud University [Nijmegen]
4 Department of Condensed Matter Physics, Weizmann Institute of Science, 76100 Rehovot

Magneto-photoluminescence measurements of individual zinc-blende GaAs/AlAs core/shell nanowires are reported. At low temperature, a strong emission line at 1.507 eV is observed under low power (nW) excitation. Measurements performed in high magnetic field allowed us to detect in this emission several lines associated with excitons bound to defect pairs. Such lines were observed before in epitaxial GaAs of very high quality, as reported by Kunzel and Ploog. This demonstrates that the optical quality of our GaAs/AlAs core/shell nanowires is comparable to the best GaAs layers grown by molecular beam epitaxy. Moreover, strong free exciton emission is observed even at room temperature. The bright optical emission of our nanowires in room temperature should open the way for numerous optoelectronic device applications.

Domaines: Supraconductivité [cond-mat.supr-con]

Paulina Plochocka, Anatolie Mitioglu, Duncan Kennedy Maude, Rikken G.L.J.A., A. Granados del Aguila, et al.. High Magnetic Field Reveals the Nature of Excitons in a Single GaAs/AlAs Core/Shell Nanowire. Nano Letters, 2013, 13, pp.2442-2447. ⟨10.1021/nl400417x⟩. ⟨hal-00877936⟩