Tuning exciton g-factors in InAs/GaAs quantum dots

Exciton g-factors have been measured for a series of single and bilayer InAs/GaAs semiconductor quantum dot (QD) ensembles emitting at wavelengths in the range 1150-1380 nm at low temperatures. A large g-factor tuning range is demonstrated, from -3 for smaller dots having a large aspect ratio to +3 for larger bilayer dots having a smaller aspect ratio and emitting at important telecommunications wavelengths. For dots emitting around 1250 nm the measured g-factors are found to be close to zero and are potentially important for future spin-based technologies.