Measurement of the effective electron mass in GaInNAs by energy-loss spectroscopy

Imaging of the electronic structure of a GaInNAs/GaAs quantum well has been investigated by mapping the variation in the plasmon frequency using an electron energy-loss spectrometer on a dedicated field emission gun scanning transmission electron microscope. Kramers–Kronig analysis of the single scattered low-loss region yields a measure of the joint effective valence electron density. The average electron density has been used to provide a direct measurement of the electron effective mass of GaInNAs. The reduced mass was found to be 0.0874m0 for a 7 nm thick Ga0.9In0.1N0.04As0.96 quantum well.