Temperature dependent piezoreflectance study of Mo1-xWxSe2 layered crystals

The temperature dependence of the spectral features in the vicinity of the direct band edge extonic transitions of Mo1-xWxSe2 layered crystals were measured in the temperature range of 25-295K using a piezoreflectance (PzR) technique. The direct band edge extonic transition energies of Mo1-xWxSe2 were determined from a detailed line-shape fit of the PzR spectra. The PzR characterization has shown tunable extonic transition continuously tuned with the W composition. The parameters that describe the temperature variation of the energies and broadening function of the excitonic transitions are evaluated and discussed. (C) 2015 AIP Publishing LLC.