Optoelectronics, Instrumentation and Data Processing. Vol. 61, No. 4, Pages 527-532, 2025

A. A. Rybak^a, b, V. D. Antsygin^a, S. A. Kuznetsov^b, c, S. L. Mikerin^a, and N. A. Nikolaev^a^,*

^aInstitute of Automation and Electrometry, Siberian Branch, Russian Academy of Sciences, Novosibirsk, 630090 Russia

^cTechnological Design Institute of Applied Microelectronics, Novosibirsk Division of the Institute of Semiconductor Physics, Siberian Branch, Russian Academy of Sciences, Novosibirsk, 630090 Russia

Abstract— Here we present the study of the complex permittivity of the Sr\({}_{0.75}\)Ba\({}_{0.25}\)Nb\({}_{2}\)O\({}_{6}\) ferroelectric crystal below 1 THz in the temperature range from \({+}25\) to \({+}200^{\circ}\)C. Notwithstanding that the relaxor is undergoing a phase transition, we have shown that the dielectric properties change slightly. A high level of stability of the dielectric permittivity was revealed for the nonpolar axis, while for the polar one it was less than 15\(\%\). The estimated terahertz electro-optic coefficient of the crystal shows the potential for the Cherenkov-type terahertz generation.

Keywords: terahertz spectroscopy, ferroelectrics, strontium barium niobate, millimeter waves

Temperature Dependence of Millimeter-Wave Dielectric Dispersion in SBN-75