Dy3+ and Tm3+ doped structurally disordered LGS Single crystals: growth, characterization, and electro- elastic property

Abstract

Optoelectronic functional crystal materials are integral to applications in fields such as aerospace and military technologies, where performance under extreme conditions is critical. This study investigates the electro-elastic properties and temperature dependent of Dy: LGS and Tm: LGS crystals, contributing to the advancement of high-temperature piezoelectric materials. Using the Czochralski method, high-quality Dy: LGS and Tm: LGS single crystals were successfully grown, and their structural, dielectric, and piezoelectric properties were extensively characterized. The results reveal that the doped crystals exhibit strong piezoelectric activity, surpassing that of quartz, with piezoelectric coefficients of 5.69 and -4.57 pC/N for Dy: LGS, and 5.72 and -5.86 pC/N for Tm: LGS, respectively. The structural analysis of the ReO8 polyhedron distortion suggests that these distortions significantly influence the piezoelectric properties. Furthermore, the electro-elastic constants and their temperature dependence were studied from room temperature to 500 °C, revealing excellent stability. The Dy: LGS and Tm: LGS crystals demonstrate notably high resistivity, with Tm: LGS crystals exhibiting the highest values. At 500°C, the resistivity values of ρ11 and ρ33 are 1.6×106 and 2.9×105 Ω·cm for Dy: LGS, and 2.1×109 and 3.2×108 Ω·cm for Tm LGS, respectively. Notably, the resistivity values for Tm: LGS crystals remain exceptionally at elevated temperatures, nearly three orders of magnitude higher than that of undoped LGS crystals at 500°C. These findings position Dy: LGS and Tm: LGS crystals as promising candidates for advanced applications requiring robust performance under extreme conditions.