Chemical bond and dielectric response of Yb2Si2O7 ceramic with low dielectric constant at GHz and THz

The exploration of high-performance dielectric ceramics with dielectric constants lower than 10 is of great significance for the next generation of wireless communication. In this study, we reported the Yb2Si2O7 (YSO) dielectric ceramics synthesized using a facile solid-state reaction technique. X-ray diffraction (XRD) and transmission electron microscopy (TEM) characterization confirmed that YSO ceramics had a monoclinic structure. At a sintering temperature of 1500 degrees C, the sintered sample reached a maximum relative density of 96% and demonstrated the best dielectric properties: dielectric constant (epsilon r) = 7.57, Qxf = 78,645 GHz (Q is quality factor, and f is the resonant frequency of 13.5 GHz), andtemperature coefficient of the resonant frequency (tau f) = -13.5 ppm/degrees C. Moreover, Raman analysis revealed that the Si-O bond dominated the lattice vibration, and the full width at half maximum (FWHM) of the strong peak at 922 cm-1 was inversely proportional to the Qxf Qxfvalue. According to the Phillips-van Vechten-Levine (P-V-L) theory, the values of Qxf Qxfand tau tau f are affected primarily by the Si-O bond, while epsilon epsilon r is influenced mainly by the Yb-O bond. YSO ceramics demonstrated excellent dielectric properties in the terahertz band (epsilon r = 8.13, Qxf= 112,758 GHz), making them promising candidates for future applications in the terahertz band.