  We study the excitonic structure of CdSe/ZnSe self assembled quantum dots
(SAQD) by magneto-photoluminescence (PL) spectroscopy. Using fixed 200 nm
apertures through a metal film, we are able to probe single narrow (200
micro-eV) spectroscopic lines emitted from CdSe quantum dots at 2K. Using
linear polarization analysis of these lines, we find that approximately half of
the quantum dots are elliptically elongated along the [110] direction. The
other half of the QDs are symmetric, with emission lines which are completely
unpolarized at zero field and exhibit no doublet structure. Using an applied
magnetic field, we obtain the diamagnetic shift and the g-factor for several
symmetric dots and find that the variation from dot to dot is random, with no
systematic dependence with emission energy. In addition, we find no correlation
between the diamagnetic shift and the g-factor.
