Magneto-optical investigations of single self-assembled InAs/InGaAlAs quantum dashes

Small mesa structures with only a few self-assembled InAs dashes for optical studies were realized by electron-beam lithography and etching techniques. The heterostructure was grown by molecular-beam epitaxy lattice-matched to an InP substrate and consists of an In0.53Ga0.23Al0.24As layer embedding in the center 3.3 monolayers of InAs. By self-assembly InAs dashes were formed. At low temperatures, narrow emission lines associated with electron-hole pairs confined in single dashes are observed. Biexciton transitions with typical binding energies of about 3.5 meV are found. The diamagnetic shift and the Zeeman splitting of single excitons are studied in magnetic fields up to 8 T in Faraday configuration. A large variation of the exciton g factor with the emission energy of quantum dashes is observed. (C) 2003 American Institute of Physics.