"Magneto-optical study of confined electrons and holes in semiconductor quantum dots"

TYPESpecial Seminar - Solid State Institute, Technion
Speaker:Mr. Giora Peniakov
Affiliation:The Physics Department and The Solid State Institute, Technion
Time:14:30 - 15:30
Location:Lidow Nathan Rosen (300)
Remark:M.Sc. Student of Professors David Gershoni and Daniel Podolsky
Abstract: We present an experimental study of the influence of externally applied magnetic field in the Faraday configuration on the photoluminescence of single InAs/GaAs self-assembled quantum dots. We comprehensively study 18 well characterized optical transitions from the same, optically excited quantum dot in various charge and occupation states. In our measurements, the emitted light was in the direction of the magnetic field and along the symmetry axis of the quantum dots. The Zeeman splitting as well as the diamagnetic shifts of these transitions are accurately measured and analyzed. The measurements are then accurately fitted using 4 g-factors for ground and first excited energy levels of the confined electron and hole. While the g-factors of the ground levels agree with previous measurements, those of the excited levels are reported here for the first time, to the best of our knowledge.

Surprisingly, the g-factor of the ground level heavy hole is reversed in sign from that of the excited heavy hole. Possible explanations for this sign reversal will be discussed.