The influence of single crystal growth conditions on the electrophysical properties of lanthanum – gallium tantalate La₃Ta_0.5Ga_5.5O₁₄ (langatate) crystals has been studied. The experiment required using polar cut samples made from crystals grown in atmospheres of argon (Ar) or argon with oxygen (Ar+O₂). The conducting coating materials were iridium (Ir), gold with а titanium sublayer (Au (Ti)) and silver with а chromium sublayer (Ag(Cr)). The temperature vs frequency dependences of the electrical admittance of langatate in an alternating electric field have been studied in the 5 Hz — 500 kHz frequency range and the 20—450 ^oC temperature range.

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