Electrical parameters of polycrystalline Sm$_{1-x}$Eu$_{x}$S rare-earth semiconductors

The electrical parameters of polycrystalline Sm$_{1-x}$Eu$_{x}$S compounds are studied. The conductivity, concentration of free electrons, their mobility, and the conductivity activation energy are measured as functions of the quantity $x$. The structural parameters of the compounds are determined. A heterostructure is fabricated with x in the range from 0 to 0.3, and the electrical voltage generated by the structure, when heated to a temperature of $T$ = 450 K, due to the thermovoltaic effect is measured. This voltage is found to be 55 mV. A method for measuring the thermally induced voltage is described. The method provides a means for separating the thermovoltaic effect from the Seebeck effect.