Effect of conductive coatings and measurement schemes on the temperature dependence of currents in α-LiIO3 crystals

Current flow characteristics in polar-cut samples of a model α-LiIO₃ crystal with various conductive coating materials were studied using various measurement schemes under an external electric field. Indium (In) and silver (Ag) were selected as the conductive coating materials. Indium foil was used for the indium conductive coatings, and silver paste was applied to the crystal for the silver conductive coatings. Measurements were performed in the temperature range from 20 to 210 °C with linear heating at a rate of no more than 3 K/min under a constant electric field of 100 V using the SKIP hardware complex with specialized ITKZ-1.0 software developed at the accredited Interdepartmental Training and Test Laboratory “Single Crystals and Stock on their Base” of NUST MISIS. The test samples were not subjected to any stimulating external influences. Temperature dependences of currents were plotted for samples with different conductive coating materials and using various measurement setups. The influence of the conductive coating material, as well as the polarity of the sample's installation in the crystal holder, on the magnitude and direction of current flow was determined. In samples with conductive In coatings, the external field enhances the currents generated in the crystal, while in samples with conductive Ag coatings, the field weakens their magnitude. During heating and cooling, the currents repeatedly reverse direction. The obtained results demonstrate the complex nature of the interaction between the conductive coating materials and the sample surfaces when an electric field is applied and the temperature increases

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