Observation of quantum-size effects in optical transmission spectra of PbTe/Pb1−xEuxTe superlattices

Abstract

Optical transmission spectra of PbTe/Pb_1−xEu_xTe (x=0.05) superlattices were measured at 300 K. The superlattices were prepared on thick Pb_1−xEu_xTe buffers grown on KCl (100) substrates using the hot wall epitaxy technique. Clear steplike absorptions corresponding to the interband electron transitions between subbands (n=1,2,3 to n=1,2,3) were observed for the first time for the PbTe/Pb_1−xEu_xTe superlattice. The experimental absorption edges agreed very well with theoretical ones calculated assuming the conduction‐band offset is equal to that of the valence band.