Change in magnetoresistance in manganese chalcogenides MnSe1-xTex from bulk to thin-film samples

The electrical and optical properties of anion-substituted antiferromagnetic semiconductors MnSe1-ХTeХ (0.1 ≤ X ≤ 0.4) in the temperature range 77-300 K and magnetic fields up to 13 kOe in bulk samples and in polycrystal- line thin films are investigated. Negative magnetoresistance was found in the MnSe1-XTeX solution in the neighbour-hood with a Néel temperature for X = 0.1 and for a composition with X = 0.2 in the paramagnetic region up to 270 K. A correlation was established between the spin-glass state and magnetoresistance for X = 0, 1 and 0.2. The optical absorption spectra were measured in the frequency range 2000 cm-1