Optical Fiber Telecommunications VA, 5th Edition

Such QD formation is observed for almost all IV/IV-, III/V-, and II/VI-

heterostructures that meet the conditions. One of the underlying processes

of formation is the “Stranski–Krastanow” growth mode; spinoidal decom-

position or submonolayer (SML) deposition are other ones [7].

• Charge carriers and excitons are strongly localized in real space for QD

volumes smaller than 10

3

nm

3

.

• There is no conservatio n of the wave vector k in zero-dimensional struc-

tures. Consequently, there is no polarization bottleneck like for structures

of higher dimensionality.

• The energy levels of charge carriers or excitons in single dots are discrete like

in atoms, showing homogeneous (Lorentzian) broadening depending on tem-

perature only.

• Recombination/absorption ...