Effect of built-in electric field in stacked type-II ZnTe/ZnSe submonolayer quantum dots: enhancement and narrowing of Aharonov-Bohm oscillations

Robust and narrow Aharonov-Bohm (AB) oscillations were observed in both intensity and energy of the mangeto-photoluminescence (PL) from stacked type-II ZnTe/ZnSe submonolayer quantum dots (QDs) grown via migration enhanced epitaxy. The narrowness and enhancement in the AB oscillations is a consequence of the built-in electric field in the system. Spectral analysis of cw magneto-PL and time-resolved PL suggest that the QD stacks size distribution is not large and thus broadening of the PL is possibly due to strong electron-phonon interaction as generally seen in bulk Zn-Se-Te systems.