Temperature dependent band offsets in PbSe/PbEuSe quantum well heterostructures

The band offsets of PbSe/Pb1-xEuxSe multi-quantum wells grown by molecular beam epitaxy are determined as a function of temperature and europium content using temperature-modulated differential transmission spectroscopy. The confined quantum well states in the valence and conduction bands are analyzed using a k·p model with envelope function approximation. From the fit of the experimental data, the normalized conduction band offset is determined as 0.45±0.15 of the band gap difference, independently of Eu content up to 14% and temperature from 20 to 300 K.